Android 8.0 相容性定義

一、簡介

本文檔列舉了裝置與 Android 8.0 相容必須滿足的要求。

「MUST」、「MUST NOT」、「REQUIRED」、「SHALL」、「SHALL NOT」、「SHOULD」、「SHOULD NOT」、「RECOMMENDED」、「MAY」和「OPTIONAL」的使用符合 IETF 標準RFC2119中定義的標準。

在本文檔中,「裝置實施者」或「實施者」是指開發運行 Android 8.0 的硬體/軟體解決方案的個人或組織。 “設備實現”或“實現是這樣開發的硬體/軟體解決方案。

若要被視為與 Android 8.0 相容,裝置實作必須滿足此相容性定義中提出的要求,包括透過引用納入的任何文件。

如果第 10 節中所述的此定義或軟體測試是沉默的、不明確的或不完整的,則設備實現者有責任確保與現有實現的兼容性。

因此, Android 開源專案既是 Android 的參考實現,也是首選實現。強烈建議設備實現者最大程度地基於 Android 開源專案提供的「上游」原始程式碼來實現其實現。雖然假設某些組件可以替換為替代實現,但強烈建議不要遵循這種做法,因為通過軟體測試將變得更加困難。實作者有責任確保與標準 Android 實作完全行為相容,包括相容性測試套件。最後,請注意,本文檔明確禁止某些組件替換和修改。

本文檔中連結的許多資源直接或間接源自 Android SDK,並且在功能上與該 SDK 文件中的資訊相同。在任何情況下,如果本相容性定義或相容性測試套件與 SDK 文件不一致,則 SDK 文件被視為具有權威性。本文檔中連結資源中提供的任何技術細節均被視為本相容性定義的一部分。

1.1 文檔結構

1.1.1.設備類型的要求

第 2 部分包含適用於特定設備類型的所有要求。第 2 節的每個小節專用於特定的設備類型。

第 2 節之後的部分列出了所有普遍適用於任何 Android 裝置實現的其他要求。這些要求在本文檔中被稱為「核心要求」。

1.1.2.需求ID

需求 ID 是為 MUST 需求分配的。

  • 僅針對必須要求分配 ID。
  • 強烈建議的要求標記為 [SR],但未分配 ID。
  • ID 包括:設備類型 ID - 條件 ID - 要求 ID(例如 C-0-1)。

每個ID的定義如下:

  • 設備類型 ID(更多資訊請參閱2. 設備類型
    • C:核心(適用於任何 Android 裝置實現的要求)
    • H:Android手持設備
    • T:Android 電視設備
    • 答:Android 汽車實施
    • Tab:Android平板電腦實現
  • 條件ID
    • 當要求是無條件時,該ID設定為0。
    • 當要求是有條件的時,為第一個條件分配1,並且在相同部分和相同設備類型內數字加1。
  • 需求ID
    • ID從1開始,在相同的部分和相同的條件下加1。

1.1.3.第 2 部分中的要求 ID

第 2 部分中的要求 ID 以對應的部分 ID 開頭,後面跟著上述要求 ID。

  • 第 2 部分中的 ID 包括:部分 ID/設備類型 ID - 條件 ID - 要求 ID(例如 7.4.3/A-0-1)。

2. 設備類型

雖然 Android 開源專案提供了可用於各種裝置類型和外形規格的軟體堆疊,但也有少數裝置類型擁有相對完善的應用程式分發生態系統。

本節介紹這些設備類型以及適用於每種設備類型的附加要求和建議。

所有不適合任何所描述的裝置類型的 Android 裝置實作仍然必須滿足本相容性定義其他部分中的所有要求。

2.1 設備配置

有關不同設備類型的硬體配置的主要差異,請參閱本節中隨後的特定於設備的要求。

2.2.手持設備要求

Android 手持裝置是指通常手持使用的 Android 裝置實現,例如 MP3 播放器、手機或平板電腦。

如果 Android 裝置實現滿足以下所有條件,則將其歸類為手持裝置:

  • 擁有提供行動性的電源,例如電池。
  • 螢幕物理對角線尺寸在 2.5 至 8 吋範圍內。

本節其餘部分的附加要求特定於 Android 手持裝置實作。

注意:不適用於 Android 平板電腦裝置的要求標示 *。

2.2.1.硬體

手持設備實現:

  • [ 7.1 .1.1/H-0-1] 螢幕的實體對角線尺寸必須至少為 2.5 吋。
  • [ 7.1 .1.3/H-SR] 強烈建議提供使用者更改顯示尺寸的能力。(螢幕密度)
  • [ 7.1 .5/H-0-1] 必須包括對由上游 Android 開源程式碼實現的遺留應用程式相容模式的支援。也就是說,設備實作不得更改啟動相容模式的觸發器或閾值,且不得更改相容模式本身的行為。
  • [ 7.2 .1/H-0-1] 必須包含對第三方輸入法編輯器 (IME) 應用程式的支援。
  • [ 7.2 .3/H-0-1] 必須提供主頁、最近存取和返回功能。
  • [ 7.2 .3/H-0-2] 必須將後退功能 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送至前台應用程式。
  • [ 7.2 .4/H-0-1] 必須支援觸控螢幕輸入。
  • [ 7.3 .1 /H-SR] 強烈建議包含 3 軸加速度計。

如果手持設備實現包括 3 軸加速計,則:

  • [ 7.3 .1/H-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

如果手持設備實作包括陀螺儀,它們:

  • [ 7.3 .4/H-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

可進行語音通話並在getPhoneType中指示除PHONE_TYPE_NONE以外的任何值的手持裝置實現:

  • [ 7.3 .8 /H] 應包括接近感測器。

手持設備實現:

  • [ 7.3 .12/H-SR] 建議支援 6 個自由度的位姿感測器。
  • [ 7.4 .3/H]應包括對藍牙和藍牙 LE 的支援。

如果手持設備實施包括按流量計費的連接,則:

  • [ 7.4 .7/H-1-1] 必須提供資料保護模式。

手持設備實現:

  • [ 7.6 .1/H-0-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分區)。
  • [ 7.6 .1/H-0-2] 當核心和使用者空間可用記憶體少於 1GB 時,必須為ActivityManager.isLowRamDevice()傳回「true」。

如果手持裝置實作是 32 位元:

  • [ 7.6 .1/H-1-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 512MB:

    • 小/普通螢幕上 280dpi 或更低*
    • 超大螢幕上的 ldpi 或更低
    • 大螢幕上的 mdpi 或更低
  • [ 7.6 .1/H-2-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 608MB:

    • 小/普通螢幕上 xhdpi 或更高*
    • 大螢幕上的 hdpi 或更高
    • 超大螢幕上的 mdpi 或更高
  • [ 7.6 .1/H-3-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 896MB:

    • 小/普通螢幕上 400dpi 或更高*
    • 大螢幕上 xhdpi 或更高
    • 超大螢幕上的 tvdpi 或更高
  • [ 7.6 .1/H-4-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1344MB:

    • 小/普通螢幕上 560dpi 或更高*
    • 大螢幕上 400dpi 或更高
    • 在超大螢幕上 xhdpi 或更高

如果手持裝置實作是 64 位元:

  • [ 7.6 .1/H-5-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 816MB:

    • 小/普通螢幕上 280dpi 或更低*
    • 超大螢幕上的 ldpi 或更低
    • 大螢幕上的 mdpi 或更低
  • [ 7.6 .1/H-6-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 944MB:

    • 小/普通螢幕上 xhdpi 或更高*
    • 大螢幕上的 hdpi 或更高
    • 超大螢幕上的 mdpi 或更高
  • [ 7.6 .1/H-7-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1280MB:

    • 小/普通螢幕上 400dpi 或更高*
    • 大螢幕上 xhdpi 或更高
    • 超大螢幕上的 tvdpi 或更高
  • [ 7.6 .1/H-8-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1824MB:

    • 小/普通螢幕上 560dpi 或更高*
    • 大螢幕上 400dpi 或更高
    • 在超大螢幕上 xhdpi 或更高

請注意,上面的「核心和用戶空間可用的記憶體」是指除了已經專用於硬體組件(例如無線電、視訊等)的任何記憶體之外提供的記憶體空間,這些硬體元件在裝置實作上不受核心控制。

手持設備實現:

  • [ 7.6 .2/H-0-1] 不得提供小於 1 GiB 的應用程式共用儲存。
  • [ 7.7 .1/H] 應包括一個支援週邊模式的 USB 連接埠。

如果手持設備實作包括支援週邊模式的 USB 端口,則:

  • [ 7.7 .1/H-1-1] 必須實作 Android 開放附件 (AOA) API。

手持設備實現:

  • [ 7.8 .1/H-0-1] 必須包括麥克風。
  • [ 7.8 .2/H-0-1] 必須有音訊輸出並聲明android.hardware.audio.output

如果手持設備實現包括對 VR 模式的支持,則它們:

  • [ 7.9 .1/H-1-1] 必須聲明android.software.vr.mode功能。

如果裝置實作聲明android.software.vr.mode功能,則:

  • [ 7.9 .1/H-2-1] 必須包含一個實作android.service.vr.VrListenerService應用程序,VR 應用程式可以透過android.app.Activity#setVrModeEnabled啟用該服務。

如果手持裝置實現能夠滿足聲明android.hardware.vr.high_performance功能標誌的所有要求,則:

  • [ 7.9 .2/-1-1] 必須聲明android.hardware.vr.high_performance功能標誌。

2.2.2.多媒體

手持設備實作必須支援以下音訊編碼:

  • [ 5.1 .1/H-0-1] AMR-NB
  • [ 5.1 .1/H-0-2] AMR-WB
  • [ 5.1 .1/H-0-3] MPEG-4 AAC 設定檔 (AAC LC)
  • [ 5.1 .1/H-0-4] MPEG-4 HE AAC 設定檔 (AAC+)
  • [ 5.1 .1/H-0-5] AAC ELD(增強型低延遲 AAC)

手持設備實作必須支援以下音訊解碼:

  • [ 5.1 .2/H-0-1] AMR-NB
  • [ 5.1 .2/H-0-2] AMR-WB

手持設備實作必須支援以下視訊編碼並使其可供第三方應用程式使用:

  • [ 5.2 /H-0-1] H.264 AVC
  • [ 5.2 /H-0-2] VP8

手持設備實作必須支援以下視訊解碼:

  • [ 5.3 /H-0-1] H.264 AVC
  • [ 5.3 /H-0-2] H.265 HEVC
  • [ 5.3 /H-0-3] MPEG-4 SP
  • [ 5.3 /H-0-4] VP8
  • [ 5.3 /H-0-5] VP9

2.2.3.軟體

手持設備實現:

  • [ 3.4 .1/H-0-1] 必須提供android.webkit.Webview API 的完整實作。
  • [ 3.4 .2/H-0-1] 必須包含用於一般使用者 Web 瀏覽的獨立瀏覽器應用程式。
  • [ 3.8 .1/H-SR] 強烈建議實作支援應用程式內固定快捷方式和小部件的預設啟動器。
  • [ 3.8 .1/H-SR] 強烈建議實作一個預設啟動器,該啟動器可以透過ShortcutManager API 快速存取第三方應用程式提供的其他捷徑。
  • [ 3.8 .1/H-SR] 強烈建議包含一個顯示應用程式圖示徽章的預設啟動器應用程式。
  • [ 3.8 .2/H-SR] 強烈建議支援第三方應用程式小工具。
  • [ 3.8 .3/H-0-1] 必須允許第三方應用程式透過NotificationNotificationManager API 類別向使用者通知值得注意的事件。
  • [ 3.8 .3/H-0-2] 必須支援豐富的通知。
  • [ 3.8 .3/H-0-3] 必須支援平視通知。
  • [ 3.8 .3/H-0-4] 必須包含通知欄,使用戶能夠透過使用者功能(例如操作按鈕或所實現的控制面板)直接控制(例如回覆、暫停、關閉、封鎖)通知在 AOSP 中。
  • [ 3.8 .4/H-SR] 強烈建議在設備上實現助手來處理協助操作

如果 Android 手持裝置實現支援鎖定螢幕,則:

  • [ 3.8 .10/H-1-1] 必須顯示鎖定畫面通知,包括媒體通知範本。

如果手持裝置實現支援安全鎖定螢幕,則它們:

  • [ 3.9 /H-1-1] 必須實施 Android SDK 文件中定義的全部裝置管理策略。

手持設備實現:

  • [ 3.10 /H-0-1] 必須支援第三方無障礙服務。
  • [ 3.10 /H-SR] 強烈建議在裝置上預先載入可存取性服務,其功能相當於或超過 Switch Access 和 TalkBack(適用於預先載入的文字轉語音引擎支援的語言)對講開放中提供的可訪問性服務來源項目
  • [ 3.11 /H-0-1] 必須支援安裝第三方 TTS 引擎。
  • [ 3.11 /H-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。
  • [ 3.13 /H-SR] 強烈建議包含快速設定 UI 元件。

如果 Android 手持裝置實現聲明FEATURE_BLUETOOTHFEATURE_WIFI支持,則:

  • [ 3.15 /H-1-1] 必須支援配套設備配對功能。

2.2.4.性能和功率

  • [ 8.1 /H-0-1]一致的幀延遲。不一致的幀延遲或渲染幀延遲的發生頻率不得超過每秒 5 幀,且應低於每秒 1 幀。
  • [ 8.1 /H-0-2]使用者介面延遲。裝置實作必須透過在 36 秒內捲動 Android 相容性測試套件 (CTS) 定義的 10K 清單條目清單來確保低延遲使用者體驗。
  • [ 8.1 /H-0-3]任務切換。當多個應用程式已啟動時,啟動後重新啟動已執行的應用程式所用時間必須少於 1 秒。

手持設備實現:

  • [ 8.2 /H-0-1] 必須確保至少 5 MB/s 的順序寫入效能。
  • [ 8.2 /H-0-2] 必須確保至少 0.5 MB/s 的隨機寫入效能。
  • [ 8.2 /H-0-3] 必須確保至少 15 MB/s 的順序讀取效能。
  • [ 8.2 /H-0-4] 必須確保至少 3.5 MB/s 的隨機讀取效能。
  • [ 8.3 /H-0-1] 所有免於應用程式待機和休眠節能模式的應用程式必須對最終使用者可見。
  • [ 8.3 /H-0-2] App Standby 和 Doze 省電模式的觸發、維護、喚醒演算法以及全域系統設定的使用不得偏離 Android 開源專案。

手持設備實現:

  • [ 8.4 /H-0-1] 必須提供每個組件的電源配置文件,該配置文件定義每個硬體組件的電流消耗值以及組件隨著時間的推移造成的近似電池消耗,如Android 開源專案網站中所述。
  • [ 8.4 /H-0-2] 必須以毫安培小時 (mAh) 為單位報告所有功耗值。
  • [ 8.4 /H-0-3] 必須報告每個行程 UID 的 CPU 功耗。 Android開源專案透過uid_cputime核心模組實作來滿足要求。
  • [ 8.4 /H-0-4] 必須透過adb shell dumpsys batterystats shell 指令向應用程式開發人員提供此電量使用量。
  • [ 8.4 /H] 如果無法將硬體組件的電源使用歸因於應用程序,則應歸因於硬體組件本身。

如果手持裝置實作包括螢幕或視訊輸出,則它們:

2.2.5。安全模型

手持設備實現:

  • [ 9.1 /H-0-1] 必須允許第三方應用程式透過android.permission.PACKAGE_USAGE_STATS權限存取使用情況統計信息,並提供用戶可訪問的機制來授予或撤銷對此類應用程式的存取權限以響應android.settings.ACTION_USAGE_ACCESS_SETTINGS意圖。

2.3.電視需求

An Android Television device refers to an Android device implementation that is an entertainment interface for consuming digital media, movies, games, apps, and/or live TV for users sitting about ten feet away (a “lean back” or “10-foot user介面").

如果 Android 裝置實現滿足以下所有條件,則將其歸類為電視:

  • 提供了一種機制來遠端控制可能距離使用者十英尺遠的顯示器上呈現的使用者介面。
  • 擁有對角線長度大於 24 吋的嵌入式螢幕顯示器或包含視訊輸出端口,例如 VGA、HDMI、DisplayPort 或用於顯示的無線端口。

本節其餘部分的附加要求特定於 Android Television 裝置實作。

2.3.1.硬體

電視設備實現:

  • [ 7.2 .2/T-0-1] 必須支援方向鍵
  • [ 7.2 .3/T-0-1] 必須提供主頁和返回功能。
  • [ 7.2 .3/T-0-2] 必須將 Back 函數 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送到前台應用程式。
  • [ 7.2 .6.1/T-0-1] 必須包含對遊戲控制器的支援並聲明android.hardware.gamepad功能標誌。
  • [ 7.2 .7/T] 應提供一個遙控器,使用者可透過此遙控器存取非觸控導航核心導航鍵輸入。

如果電視設備實作包含陀螺儀,則它們:

  • [ 7.3 .4/T-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

電視設備實現:

  • [ 7.4 .3/T-0-1] 必須支援藍牙和藍牙 LE。
  • [ 7.6 .1/T-0-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)。

如果電視設備實現是 32 位元:

  • [ 7.6 .1/T-1-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 896MB:

    • 小/普通螢幕上 400dpi 或更高
    • 大螢幕上 xhdpi 或更高
    • 超大螢幕上的 tvdpi 或更高

如果電視設備實現是 64 位元:

  • [ 7.6 .1/T-2-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1280MB:

    • 小/普通螢幕上 400dpi 或更高
    • 大螢幕上 xhdpi 或更高
    • 超大螢幕上的 tvdpi 或更高

請注意,上面的「核心和用戶空間可用的記憶體」是指除了已經專用於硬體組件(例如無線電、視訊等)的任何記憶體之外提供的記憶體空間,這些硬體元件在裝置實作上不受核心控制。

電視設備實現:

  • [ 7.8 .1/T] 應包括麥克風。
  • [ 7.8 .2/T-0-1] 必須有音訊輸出並聲明android.hardware.audio.output

2.3.2.多媒體

電視設備實作必須支援以下音訊編碼:

  • [ 5.1 /T-0-1] MPEG-4 AAC 設定檔 (AAC LC)
  • [ 5.1 /T-0-2] MPEG-4 HE AAC 設定檔 (AAC+)
  • [ 5.1 /T-0-3] AAC ELD(增強型低延遲 AAC)

電視設備實作必須支援以下視訊編碼:

  • [ 5.2 /T-0-1] H.264 AVC
  • [ 5.2 /T-0-2] VP8

電視設備實現:

  • [ 5.2 .2/T-SR] 強烈建議支援 720p 和 1080p 解析度視訊的 H.264 編碼。
  • [ 5.2 2/T-SR] 強烈建議支援每秒 30 幀 (fps) 的 1080p 解析度影片的 H.264 編碼。

電視設備實作必須支援以下視訊解碼:

  • [ 5.3 /T-0-1] H.264 AVC
  • [ 5.3 /T-0-2] H.265 HEVC
  • [ 5.3 /T-0-3] MPEG-4 SP
  • [ 5.3 /T-0-4] VP8
  • [ 5.3 /T-0-5] VP9

強烈建議電視設備實現支援以下視訊解碼:

  • [ 5.3 /T-SR] MPEG-2

如果電視設備實現支援 H.264 解碼器,則它們:

  • [ 5.3 .4/T-1-1] 必須支援 High Profile Level 4.2 和 HD 1080p(60 fps)解碼設定檔。
  • [ 5.3 .4/T-1-2] 必須能夠使用下表所示的兩種 HD 設定檔進行解碼,並使用 Baseline Profile、Main Profile 或 High Profile Level 4.2 進行編碼

如果電視設備實現支援 H.265 編解碼器和 HD 1080p 解碼配置文件,則:

  • [ 5.3 .5/T-1-1] 必須支援主設定檔等級 4.1 主層。
  • [ 5.3 .5/T-SR] 強烈建議支援 HD 1080p 的 60 fps 視訊幀率。

如果電視設備實現支援 H.265 編解碼器和 UHD 解碼配置文件,則:

  • [ 5.3 .5/T-2-1] 編解碼器必須支援 Main10 第 5 級主層設定檔。

如果電視設備實作支援 VP8 編解碼器,則它們:

  • [ 5.3 .6/T-1-1] 必須支援 HD 1080p60 解碼設定檔。

如果電視設備實作支援 VP8 編解碼器並支援 720p,則:

  • [ 5.3 .6/T-2-1] 必須支援 HD 720p60 解碼設定檔。

如果電視設備實現支援 VP9 編解碼器和 UHD 視訊解碼,則:

  • [ 5.3 .7/T-1-1] 必須支援 8 位元顏色深度,並且應該支援 VP9 設定檔 2(10 位元)。

如果電視設備實作支援 VP9 編解碼器、1080p 設定檔和 VP9 硬體解碼,則:

  • [ 5.3 .7/T-2-1] 必須支援 1080p 的 60 fps。

電視設備實現:

  • [ 5.8 /T-SR] 強烈建議支援安全流的同步解碼。至少,強烈建議同時解碼兩個串流。

如果設備實現是 Android Television 設備並支援 4K 分辨率,則:

  • [ 5.8 /T-1-1] 所有有線外部顯示器必須支援 HDCP 2.2。

如果電視設備實現不支援 4K 分辨率,則:

  • [ 5.8 /T-2-1] 所有有線外部顯示器必須支援 HDCP 1.4。

電視設備實現:

  • [ 5.5 .3/T-0-1] 必須支援系統主音量及支援輸出上的數位音訊輸出音量衰減,壓縮音訊直通輸出除外(裝置上未進行音訊解碼)。

2.3.3.軟體

電視設備實現:

  • [ 3 /T-0-1] 必須聲明功能android.software.leanbackandroid.hardware.type.television
  • [ 3.4 .1/T-0-1] 必須提供android.webkit.Webview API 的完整實作。

如果 Android Television 裝置實作支援鎖定螢幕,則:

  • [ 3.8 .10/T-1-1] 必須顯示鎖定畫面通知,包括媒體通知範本。

電視設備實現:

  • [ 3.8 .14/T-SR] 強烈建議支持畫中畫 (PIP) 模式多視窗。
  • [ 3.10 /T-0-1] 必須支援第三方無障礙服務。
  • [ 3.10 /T-SR] 強烈建議在裝置上預先載入輔助服務,其功能相當於或超過 Switch Access 和 TalkBack(適用於預先載入的文字轉語音引擎支援的語言)對講開放中提供的輔助服務來源專案.

如果電視設備實現報告功能android.hardware.audio.output ,則:

  • [ 3.11 /T-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。
  • [ 3.11 /T-1-1] 必須支援安裝第三方 TTS 引擎。

電視設備實現:

  • [ 3.12 /T-0-1] 必須支援電視輸入框架。

2.2.4.性能和功率

  • [ 8.1 /T-0-1]一致的幀延遲。不一致的幀延遲或渲染幀延遲的發生頻率不得超過每秒 5 幀,且應低於每秒 1 幀。
  • [ 8.2 /T-0-1] 必須確保至少 5MB/s 的順序寫入效能。
  • [ 8.2 /T-0-2] 必須確保至少 0.5MB/s 的隨機寫入效能。
  • [ 8.2 /T-0-3] 必須確保至少 15MB/s 的順序讀取效能。
  • [ 8.2 /T-0-4] 必須確保至少 3.5MB/s 的隨機讀取效能。

  • [ 8.3 /T-0-1] 所有免於應用程式待機和打盹節能模式的應用程式必須對最終用戶可見。

  • [ 8.3 /T-0-2] App Standby 和 Doze 省電模式的觸發、維護、喚醒演算法以及全域系統設定的使用不得偏離 Android 開源專案。

電視設備實現:

  • [ 8.4 /T-0-1] 必須提供每個組件的電源配置文件,該配置文件定義每個硬體組件的電流消耗值以及組件隨著時間的推移造成的近似電池消耗,如Android 開源專案網站中所述。
  • [ 8.4 /T-0-2] 必須以毫安培小時 (mAh) 為單位報告所有功耗值。
  • [ 8.4 /T-0-3] 必須報告每個行程 UID 的 CPU 功耗。 Android開源專案透過uid_cputime核心模組實作來滿足要求。
  • [ 8.4 /T] 如果無法將硬體組件的電源使用歸因於應用程序,則應歸因於硬體組件本身。
  • [ 8.4 /T-0-4] 必須透過adb shell dumpsys batterystats shell 指令向應用程式開發人員提供此電量使用量。

2.4.手錶要求

Android Watch 裝置是指設計用於配戴在身體上(可能戴在手腕上)的 Android 裝置實現。

如果 Android 裝置實作符合以下所有條件,則被歸類為 Watch:

  • 螢幕的物理對角線長度在 1.1 到 2.5 吋之間。
  • 提供可佩戴在身上的機構。

本節其餘部分的附加要求特定於 Android Watch 裝置實作。

2.4.1.硬體

觀看設備實現:

  • [ 7.1 .1.1/W-0-1] 螢幕的實體對角線尺寸必須在 1.1 到 2.5 吋之間。

  • [ 7.2 .3/W-0-1] 必須具有可供使用者使用的 Home 功能和 Back 功能,除非處於UI_MODE_TYPE_WATCH狀態。

  • [ 7.2 .4/W-0-1] 必須支援觸控螢幕輸入。

  • [ 7.3 .1 /W-SR] 強烈建議包含 3 軸加速度計。

  • [ 7.4 .3/W-0-1] 必須支援藍牙。

  • [ 7.6 .1/W-0-1] 必須有至少 1GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)

  • [ 7.6 .1/W-0-2] 必須至少有 416MB 記憶體可供核心和使用者空間使用。

  • [ 7.8 .1/W-0-1] 必須包括麥克風。

  • [ 7.8 .2/W] 可以但不應該有音訊輸出。

2.4.2.多媒體

無額外要求。

2.4.3.軟體

觀看設備實現:

  • [ 3 /W-0-1] 必須宣告功能android.hardware.type.watch
  • [ 3 /W-0-2] 必須支援 uiMode = UI_MODE_TYPE_WATCH

觀看設備實現:

  • [ 3.8 .4/W-SR] 強烈建議在設備上實現助手來處理協助操作

觀看聲明android.hardware.audio.output功能標誌的裝置實作:

  • [ 3.10 /W-1-1] 必須支援第三方無障礙服務。
  • [ 3.10 /W-SR] 強烈建議在裝置上預先載入輔助服務,其功能相當於或超過 Switch Access 和 TalkBack(適用於預先載入的文字轉語音引擎支援的語言)對講開放中提供的輔助服務來源專案.

如果 Watch 裝置實作報告了 android.hardware.audio.output 功能,則:

  • [ 3.11 /W-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。

  • [ 3.11 /W-0-1] 必須支援安裝第三方 TTS 引擎。

2.5.汽車要求

Android Automotive 實作是指運行 Android 作為部分或全部系統和/或資訊娛樂功能的作業系統的車輛主機。

如果 Android 裝置實作聲明了android.hardware.type.automotive功能或滿足以下所有條件,則它們被歸類為汽車。

  • 作為汽車的一部分嵌入或可插入汽車。
  • 使用駕駛座排中的畫面作為主顯示幕。

本節其餘部分的附加要求是特定於 Android Automotive 裝置實作。

2.5.1.硬體

汽車設備實現:

  • [ 7.1 .1.1/A-0-1] 螢幕的實體對角線尺寸必須至少為 6 吋。
  • [ 7.1 .1.1/A-0-2] 螢幕尺寸佈局必須至少為 750 dp x 480 dp。

  • [ 7.2 .3/A-0-1] 必須提供主頁功能,並且可以提供返回和最近使用的功能。

  • [ 7.2 .3/A-0-2] 必須將 Back 函數 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送到前台應用程式。

  • [ 7.3 .1 /A-SR] 強烈建議包含 3 軸加速度計。

如果汽車設備實現包括 3 軸加速度計,則:

如果汽車設備實作包括 GPS/GNSS 接收器並透過android.hardware.location.gps功能標誌向應用程式報告該功能:

  • [ 7.3 .3/A-1-1] GNSS 技術世代必須是「2017 年」或更晚的年份。

如果汽車設備實作包括陀螺儀,則它們:

  • [ 7.3 .4/A-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

汽車設備實現:

  • [ 7.3 .11/A] 應提供目前齒輪作為SENSOR_TYPE_GEAR

汽車設備實現:

  • [ 7.3 .11.2/A-0-1] 必須支援定義為SENSOR_TYPE_NIGHT日間/夜間模式。
  • [ 7.3 .11.2/A-0-2] SENSOR_TYPE_NIGHT標誌的值必須與儀表板日/夜模式一致,並且應該基於環境光感測器輸入。
  • 底層環境光感測器可能與光度計相同。

  • [ 7.3 .11.3/A-0-1] 必須支援定義為SENSOR_TYPE_DRIVING_STATUS駕駛狀態,當車輛完全停止並停放時,預設值為DRIVE_STATUS_UNRESTRICTED 。設備製造商有責任根據適用於產品出貨市場的所有法律和法規來配置SENSOR_TYPE_DRIVING_STATUS

  • [ 7.3 .11.4/A-0-1] 必須提供定義為SENSOR_TYPE_CAR_SPEED車輛速度。

  • [ 7.4 .3/A-0-1] 必須支援藍牙並且應該支援藍牙 LE。

  • [ 7.4 .3/A-0-2] Android Automotive 實作必須支援以下藍牙設定檔:
    • 透過免持模式 (HFP) 撥打電話。
    • 透過音訊分發設定檔 (A2DP) 進行媒體播放。
    • 透過遠端控製設定檔 (AVRCP) 進行媒體播放控制。
    • 使用電話簿存取設定檔 (PBAP) 共用聯絡人。
  • [ 7.4 .3 /A] 應支援訊息存取設定檔(MAP)。

  • [ 7.4 .5/A] 應包括基於蜂窩網路的數據連接的支援。

  • [ 7.6 .1/A-0-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)。

如果汽車設備實現是 32 位元:

  • [ 7.6 .1/A-1-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 512MB:

    • 小/普通螢幕上 280dpi 或更低
    • 超大螢幕上的 ldpi 或更低
    • 大螢幕上的 mdpi 或更低
  • [ 7.6 .1/A-1-2] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 608MB:

    • 小/普通螢幕上的 xhdpi 或更高
    • 大螢幕上的 hdpi 或更高
    • 超大螢幕上的 mdpi 或更高
  • [ 7.6 .1/A-1-3] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 896MB:

    • 小/普通螢幕上 400dpi 或更高
    • 大螢幕上 xhdpi 或更高
    • 超大螢幕上的 tvdpi 或更高
  • [ 7.6 .1/A-1-4] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1344MB:

    • 小/普通螢幕上 560dpi 或更高
    • 大螢幕上 400dpi 或更高
    • 在超大螢幕上 xhdpi 或更高

如果汽車設備實現是 64 位元:

  • [ 7.6 .1/A-2-1] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 816MB:

    • 小/普通螢幕上 280dpi 或更低
    • 超大螢幕上的 ldpi 或更低
    • 大螢幕上的 mdpi 或更低
  • [ 7.6 .1/A-2-2] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 944MB:

    • 小/普通螢幕上的 xhdpi 或更高
    • 大螢幕上的 hdpi 或更高
    • 超大螢幕上的 mdpi 或更高
  • [ 7.6 .1/A-2-3] 如果使用以下任何密度,則核心和使用者空間可用的記憶體必須至少為 1280MB:

    • 小/普通螢幕上 400dpi 或更高
    • xhdpi或更高的大螢幕
    • TVDPI或更高的大螢幕
  • [ 7.6 .1/a-2-4]如果使用以下任何密度,則核心和使用者空間的記憶體必須至少為1824MB:

    • 小/普通螢幕上的560DPI或更高
    • 大螢幕上的400DPI或更高
    • xhdpi或更高的大螢幕

請注意,上面的「可用的記憶體和用戶空間的記憶體」是指除了已經專用於硬體元件(例如無線電,視訊等)的任何記憶體之外提供的記憶體空間,而這些記憶體不在核心對裝置實現的控制下。

汽車設備實現:

  • [ 7.7 .1/a]應包括支援外圍模式的USB連接埠。

汽車設備實現:

  • [ 7.8 .1/A-0-1]必須包括麥克風。

汽車設備實現:

  • [ 7.8 .2/a-0-1]必須具有音訊輸出並聲明android.hardware.audio.output

2.5.2.多媒體

汽車設備實作必須支援以下音訊編碼:

  • [ 5.1 /a-0-1] MPEG-4 AAC設定檔(AAC LC)
  • [ 5.1 /a-0-2] MPEG-4 HE AAC概況(AAC+)
  • [ 5.1 /A-0-3] AAC ELD(增強的低延遲AAC)

汽車設備實作必須支援以下視訊編碼:

  • [ 5.2 /a-0-1] H.264 AVC
  • [ 5.2 /a-0-2] VP8

汽車設備實作必須支援以下視訊解碼:

  • [ 5.3 /a-0-1] H.264 AVC
  • [ 5.3 /A-0-2] MPEG-4 SP
  • [ 5.3 /a-0-3] VP8
  • [ 5.3 /a-0-4] VP9

強烈建議使用汽車設備實作來支援以下視訊解碼:

  • [ 5.3 /A-SR] H.265 HEVC

2.5.3.軟體

汽車設備實現:

  • [ 3 /A-0-1]必須宣告功能android.hardware.type.automotive
  • [ 3 /a-0-2]必須支援uimode = ui_mode_type_car
  • [ 3 /A-0-3] Android汽車實作必須支援android.car.*名稱空間中的所有公共API。

  • [ 3.4 .1/a-0-1]必須提供android.webkit.Webview API的完整實作。

  • [ 3.8 .3/a-0-1]必須顯示使用通知的通知。當第三方應用程式要求時, Notification.CarExtender API。

  • [ 3.8 .4/A-0-1]必須在設備上實施助手來處理輔助操作

  • [ 3.14 /A-0-1]必須包含一個UI框架,以使用第3.14節所述的媒體API支援第三方應用程式。

2.2.4.性能和力量

汽車設備實現:

  • [ 8.3 /a-0-1]必須讓最終用戶可以看到所有豁免應用程式備用和省力動力模式的應用程式。
  • [ 8.3 /a-0-2]觸發,維護,喚醒演算法以及應用程式備用和撥打功率的全域系統設定的使用不得偏離Android開源專案。

  • [ 8.4 /A-0-1]必須提供每個組件功率配置文件,該輪廓定義每個硬體組件的當前消耗值以及由組件隨時間推移所致的電池耗盡,如Android開源專案網站所記錄的那樣。

  • [ 8.4 /A-0-2]必須以毫安培小時(MAH)報告所有功耗值。
  • [ 8.4 /A-0-3]必須根據每個製程的UID報告CPU功耗。 Android開源專案透過uid_cputime核心模組實現滿足了需求。
  • [ 8.4 /a]如果無法將硬體組件用法歸因於應用程序,則應歸因於硬體組件本身。
  • [ 8.4 /a-0-4]必須透過adb shell dumpsys batterystats shell命令將此電源提供給應用程式開發人員。

2.2.5。安全模型

如果汽車設備實現包括多個用戶,則它們:

  • [ 9.5 /A-1-1]必須包含一個允許車輛系統提供的功能的來賓帳戶,而無需使用者登入。

汽車設備實現:

  • [ 9.14 /a-0-1]必須來自Android Framework車輛子系統(例如,允許清單允許的訊息類型和訊息來源)的網務訊息。
  • [ 9.14 /a-0-2]必須監視拒絕來自Android框架或第三方應用程式的服務攻擊。這種防禦惡意軟體會淹沒車輛網路的流量,這可能會導致車輛子系統故障。

2.6。平板電腦要求

Android平板電腦設備是指Android設備實現,通常是透過雙手握住而不是用夾具形式的工具來使用的Android設備。

如果Android設備實現符合以下所有標準,則將其歸類為平板電腦:

  • 具有提供移動性的電源,例如電池。
  • 實體對角線螢幕尺寸在7到18英吋的範圍內。

平板設備實現與手持設備實現相似。該部分中的例外和 *在本節中指定為參考。

2.4.1.硬體

螢幕尺寸

  • [ 7.1 .1.1/tab-0-1]必須在7到18英吋的範圍內具有一個螢幕。

最小記憶體和儲存(第7.6.1節)

在手持要求中列出的小/普通螢幕列出的螢幕密度不適用於平板電腦。

USB外圍模式(第7.7.1節)

如果平板電腦設備實現包括支援外圍模式的USB端口,則它們:

  • [ 7.7.1 /tab]可以實作Android Open Accessory(AOA)API。

虛擬實境模式(第7.9.1節)

虛擬實境高效能(第7.9.2節)

虛擬實境要求不適用於平板電腦。

3、軟體

3.1.託管 API 相容性

託管的 Dalvik 字節碼執行環境是 Android 應用程式的主要工具。 Android 應用程式介面 (API) 是向在託管執行時間環境中運行的應用程式公開的一組 Android 平台介面。

  • [C-0-1]裝置實作必須提供完整的實現,包括所有已記錄的行為,包括Android SDK所示的任何已記錄的API或上游Android原始程式碼中使用「 @Systemapi」標記的任何API。

  • [C-0-2]設備實作必須支援/保留以TESTAPI註釋(@testapi)標記的所有類,方法和相關元素。

  • [C-0-3]裝置實作不得省略任何託管的API,更改API介面或簽名,偏離已記錄的行為,或包括NO-OPS,除非該相容性定義明確允許。

  • [C-0-4]裝置實作仍然必須保持API的存在並以合理的方式行事,即使省略了Android包含API的某些硬體功能。有關此場景的具體要求,請參閱第 7 節

3.1.1.安卓擴充

Android包括在保留相同的API級版本的同時擴展託管API的支援。

  • [C-0-1] Android設備的實現必須預緊額的AOSP實現,共享庫ExtShared和Services ExtServices具有高於或等於每個API級別允許的最小版本。例如,Android 7.0裝置實現,運行API等級24必須至少包含版本1。

3.2.軟 API 相容性

除了第3.1節的託管API外,Android還以意圖,權限和Android應用程式的類似方面的形式還包括一個僅在應用程式編譯時執行的Android應用程式的形式。

3.2.1.權限

  • [C-0-1]設備實施者必須支援並執行許可參考頁所記錄的所有權限常數。請注意,第 9 節列出了與 Android 安全模型相關的其他要求。

3.2.2.建構參數

Android API包括旨在描述目前裝置的Android.os.build類別上的許多常數。

  • [C-0-1]為了在設備實現之間提供一致的,有意義的值,下表包括這些值必須符合的這些值的格式的其他限制。
範圍細節
版本.發布目前執行的 Android 系統的版本,採用人類可讀的格式。此欄位必須具有8.0中定義的字串值之一。
版本.SDK目前執行的 Android 系統的版本,採用第三方應用程式程式碼可存取的格式。對於Android 8.0,此欄位必須具有整數值8.0_INT。
版本.SDK_INT目前執行的 Android 系統的版本,採用第三方應用程式程式碼可存取的格式。對於Android 8.0,此欄位必須具有整數值8.0_INT。
版本.增量裝置實現者選擇的值,以人類可讀的格式指定目前正在執行的 Android 系統的特定版本。該值不得重複用於提供給最終用戶的不同建置。此欄位的典型用途是指示使用哪個版本號或原始碼控制變更標識符來產生版本。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
木板設備實現者選擇的值,以人類可讀的格式標識設備使用的特定內部硬體。此欄位的一個可能用途是指示為設備供電的板的特定版本。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 _-]+$」。
品牌反映最終用戶所知的與設備相關的品牌名稱的值。必須採用人類可讀的格式,並且應該代表設備的製造商或設備銷售的公司品牌。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 _-]+$」。
支援_ABIS本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
SUPPORTED_32_BIT_ABIS本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
SUPPORTED_64_BIT_ABIS本機程式碼的第二指令集(CPU 類型 + ABI 約定)的名稱。請參閱第 3.3 節。本機 API 相容性
CPU_ABI本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
CPU_ABI2本機程式碼的第二指令集(CPU 類型 + ABI 約定)的名稱。請參閱第 3.3 節。本機 API 相容性
裝置設備實現者選擇的值,包含標識硬體功能配置和設備工業設計的開發名稱或代號。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 _-]+$」。此設備名稱在產品的使用壽命中不得更改。
指紋唯一標識此建置的字串。它應該是合理的人類可讀的。它必須遵循以下模板:

$(品牌)/$(product)/
$(設備):$(version.Release)/$(id)/$(version.incremental):$(type)/$(tags)

例如:

Acme/ryproduct/
mydevice:8.0/lmyxx/3359:使用者debug/test-keys

指紋不得包含空白字元。如果上述模板中包含的其他字段具有空白字符,則必須在構建指紋中將它們替換為另一個字符,例如下劃線(“_”)字符。此欄位的值必須可編碼為 7 位元 ASCII。

硬體硬體的名稱(來自核心命令列或/proc)。它應該是合理的人類可讀的。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 _-]+$」。
主持人一個字串,以人類可讀的格式唯一標識建構建構的主機。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
ID設備實現者選擇的標識符,用於引用特定版本,採用人類可讀的格式。該欄位可以與 android.os.Build.VERSION.INCRMENTAL 相同,但應該是一個對於最終用戶區分軟體版本足夠有意義的值。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 ._-]+$」。
製造商產品原始設備製造商 (OEM) 的商品名稱。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。該領域在產品的生命週期內不得改變。
模型設備實現者選擇的值,包含最終使用者已知的設備名稱。此名稱應與設備行銷和銷售給最終用戶時使用的名稱相同。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。該領域在產品的生命週期內不得改變。
產品設備實施者選擇的值,包含特定產品 (SKU) 的開發名稱或程式碼名稱,該產品在同一品牌中必須是唯一的。必須是人類可讀的,但不一定供最終用戶查看。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 _-]+$」。該產品名稱在產品的一生中不得更改。
串口一個硬體序號,必須在具有相同型號和製造商的設備之間可用且獨特。此欄位的值必須編碼為7位元ASCII,並且符合正規表示式「^([A-ZA-Z0-9] {6,20}})$。
標籤由設備實現者選擇的以逗號分隔的標籤列表,可進一步區分建置。此欄位必須具有與三種典型 Android 平台簽章配置相對應的值之一:release-keys、dev-keys、test-keys。
時間表示建構發生時間的時間戳記的值。
類型由設備實現者選擇的值,指定建置的運行時配置。此欄位必須具有與三種典型 Android 運行時配置相對應的值之一:user、userdebug 或 eng。
使用者產生建置的使用者(或自動使用者)的名稱或使用者 ID。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
Security_Patch表示建構的安全補丁等級的值。它必須表明該構建並不容易受到透過指定的Android公共安全公告所描述的任何問題的影響。它必須採用格式[yyyy-mm-dd],與Android公共安全公告Android Security Advisory中記錄的定義字串匹配,例如「 2015-11-01」。
base_os代表建構指紋參數的值,除了Android公共安全公告中提供的補丁外,該值與該建置相同。它必須報告正確的值,如果不存在這種構建,請報告一個空字串(“”)。
引導程式裝置實現者選擇的值,以人為可讀取的格式識別裝置中使用的特定內部引導程式版本。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 ._-]+$」。
getradioversion()必須(或返回)設備實現者選擇的值,該值以人為可讀取的格式識別設備中使用的特定內部無線電/數據機版本。如果裝置沒有任何內部收音機/數據機,則必須傳回null。此欄位的值必須編碼為7位元ASCII,並符合正規表示式「^[A-ZA-Z0-9 ._-,]+$。

3.2.3.意圖相容性

3.2.3.1.核心應用意圖

Android 意圖允許應用程式元件向其他 Android 元件請求功能。 Android 上游項目包括被視為核心 Android 應用程式的應用程式列表,這些應用程式實現了多種意圖模式來執行常見操作。

  • [C-0-1]設備實作必須包括這些應用程序,服務組件或至少一個處理程序,以適用於AOSP中以下核心Android應用程式定義的所有公共意圖過濾模式:

    • 英式鐘
    • 瀏覽器
    • 日曆
    • 聯絡方式
    • 畫廊
    • 全球搜尋
    • 啟動器
    • 音樂
    • 設定
3.2.3.2.意圖解析
  • [C-0-1]由於Android是一個可擴展的平台,設備實作必須允許第3.2.3.1節中引用的每個意圖模式被第三方應用程式覆蓋。預設情況下,上游Android開源實作允許這樣做。
  • [C-0-2] DVICE實施者不得將特殊特權附加到系統應用程式對這些意圖模式的使用,或防止第三方應用程式與這些模式的結合並控制這些模式。該禁令專門包括,但不限於禁用「選擇器」使用者介面,該介面允許用戶在所有處理相同意圖模式的多個應用程式之間進行選擇。

  • [C-0-3]設備實作必須為使用者提供使用者介面,以修改意圖的預設活動。

  • 但是,裝置實作可能會為特定的URI模式提供預設活動(例如http://play.google.com),當預設活動提供更具體的屬性時,請使用資料URI。例如,指定資料URI「 http://www.android.com」的意圖過濾模式比「 http:// http://」的核心意圖模式更具體。

Android還包含第三方應用程式的機制,可以聲明某些類型的Web URI意圖的權威預設應用程式連結行為。當應用程式的意圖過濾模式定義此類權威聲明時,設備實作:

  • [C-0-4]必須嘗試透過執行在上游Android開源專案中實現的數位資產連結規格中定義的驗證步驟來驗證任何意圖過濾器。
  • [C-0-5]必須嘗試在安裝應用程式期間驗證意圖過濾器,並將所有成功驗證的URI意圖過濾器設定為其URIS的預設應用程式處理程序。
  • 如果成功驗證,但其他候選URI過濾器失敗驗證,則可能將特定的URI意圖過濾器設定為其URI的預設應用程式處理程序。如果裝置實作執行此操作,則必須在「設定」功能表中為使用者提供適當的per-uri模式。
  • 必須在設定中為用戶提供每個應用程式應用程式連結控件,如下所示:
    • [C-0-6]使用者必須能夠整體上覆蓋應用程式的預設應用程式連結行為:始終打開,始終詢問或永遠不會打開,必須適用於所有候選URI意圖均等過濾器。
    • [C-0-7]使用者必須能夠查看候選URI意圖過濾器的清單。
    • 此設備實作可以使用戶能夠以每次大量過濾器成功驗證特定的候選URI意圖過濾器。
    • [C-0-8]裝置實作必須為使用者提供檢視和覆蓋特定候選URI意圖過濾器的能力,如果裝置實作使某些候選URI意圖過濾器成功驗證,而其他人則可能會失敗。
3.2.3.3.意圖命名空間
  • [C-0-1]裝置實作不得包含任何使用Android中的動作,類別或其他金鑰字串的新意圖或廣播意圖模式來尊重任何新意圖或廣播的模式。或com.android。命名空間。
  • [C-0-2]裝置實現者不得包含任何使用動作,類別或其他金鑰字串的新意圖或廣播意圖模式來尊重任何新意圖或廣播意圖模式,否則不得包含任何Android元件。
  • [C-0-3]設備實現者不得更改或擴展第3.2.3.1節中列出的核心應用程式所使用的任何意圖模式。
  • 設備實作可以包括使用與其自己的組織明確相關的命名空間的意圖模式。該禁止類似於3.6 節中針對 Java 語言類別指定的禁止。
3.2.3.4.廣播意圖

第三方應用程式依靠平台廣播某些意圖,以通知它們硬體或軟體環境的變化。

設備實現:

  • [C-0-1]必須依照SDK文件中所述的適當系統事件來廣播公眾廣播意圖。請注意,此要求與第3.5節沒有衝突,因為SDK文件中也描述了背景應用程式的限制。
3.2.3.5.預設應用程式設定

Android 包含的設定可讓用戶輕鬆選擇預設應用程序,例如主螢幕或簡訊。

在有意義的情況下,設備實作必須提供類似的設定選單,並與 SDK 文件中所述的意圖過濾器模式和 API 方法相容,如下所示。

如果裝置實作報表android.software.home_screen ,則它們:

如果裝置實作報表android.hardware.telephony ,它們:

如果裝置實作報表android.hardware.nfc.hce ,則它們:

如果裝置實作報表android.hardware.telephony ,它們:

如果設備實作支援VoiceIntractionservice,則它們:

3.2.4.輔助顯示的活動

如果設備實作允許在輔助顯示器上啟動正常的Android活動,則它們:

  • [C-1-1]必須設定android.software.activities_on_secondary_displays功能標誌。
  • [C-1-2] 必須確保 API 相容性,類似於在主顯示幕上執行的活動。
  • [C-1-3]必須將新活動與啟動其啟動的活動相同的顯示,而新活動是在不透過ActivityOptions.setLaunchDisplayId() API指定目標顯示的情況下啟動的。
  • [C-1-4]當有Display.FLAG_PRIVATE標誌的顯示時,必須銷毀所有活動。
  • [C-1-5]如果調整顯示本身,則必須相應地調整VirtualDisplay上的所有活動。
  • 當文字輸入欄位專注於輔助顯示時,可以在主顯示器上顯示IME(輸入方法編輯器,一個使用戶輸入文字的使用者控制項)。
  • 應在支援觸控或鍵輸入時獨立於主顯示器上的輸入重點。
  • 應具有與該顯示相對應的android.content.res.Configuration ,以便顯示,正確操作並保持相容性,如果在輔助顯示上啟動了活動。

如果裝置實作允許在輔助顯示上啟動正常的Android活動,並且主要和次要顯示具有不同的Android.util.displaymetrics

  • [C-2-1]不可避免的活動(在AndroidManifest.xml中具有resizeableActivity=false )和針對API等級23或更低的應用程式在輔助顯示時不得允許。

如果裝置實作允許在輔助顯示器上啟動正常的Android 活動,且輔助顯示器具有android.view.Display.FLAG_PRIVATE標誌:

  • [C-3-1] 只有該顯示、系統以及該顯示上已存在的活動的擁有者才能夠啟動該顯示。每個人都可以啟動具有android.view.Display.FLAG_PUBLIC標誌的顯示器。

3.3.本機 API 相容性

本機程式碼相容性具有挑戰性。因此,設備實現者是:

  • [SR]強烈建議使用下游Android開源專案中列出的程式庫的實作。

3.3.1.應用程式二進位接口

託管 Dalvik 字節碼可以呼叫應用程式.apk檔案中提供的本機程式碼,作為針對適當設備硬體架構編譯的 ELF .so檔。由於本機程式碼高度依賴底層處理器技術,Android 在 Android NDK 中定義了許多應用程式二進位介面 (ABI)。

設備實現:

  • [C-0-1]必須與一個或多個定義的ABI相容,並與Android NDK實現相容性。
  • [C-0-2] 必須支援在託管環境中執行的程式碼,以使用標準 Java 本機介面 (JNI) 語意呼叫本機程式碼。
  • [C-0-3] 必須與下面列表中每個必需的庫來源相容(即標頭相容)和二進位相容(對於 ABI)。
  • [C-0-4]如果支援任何64位元ABI,則必須支援等效的32位元ABI。
  • [C-0-5] MUST accurately report the native Application Binary Interface (ABI) supported by android.os.Build.SUPPORTED_64_BIT_ABIS device, via the android.os.Build.SUPPORTED_ABIS , android.os.Build.SUPPORTED_32_BIT_ABIS para.P.A.S.S. ,每個逗號分開的ABIS列表從最多到最不受歡迎的列表。
  • [C-0-6]必須透過上述參數報告,只有在Android NDK ABI管理文件的最新版本中記錄和描述的ABI,並且必須包括對高級SIMD (AKA NEON)擴展的支援。
  • [C-0-7] 必須讓下列所有提供本機 API 的函式庫可供包含本機程式碼的應用程式使用:

    • libaaudio.so(Aaudio本地音訊支援)
    • libandroid.so(原生 Android 活動支援)
    • libc(C 庫)
    • libcamera2ndk.so
    • libdl(動態連結器)
    • libEGL.so(原生 OpenGL 表面管理)
    • libGLESv1_CM.so (OpenGL ES 1.x)
    • libGLESv2.so(OpenGL ES 2.0)
    • libGLESv3.so (OpenGL ES 3.x)
    • libicui18n.so
    • libicuuc.so
    • libjnigraphics.so
    • liblog(Android 日誌記錄)
    • libmediandk.so(原生媒體 API 支援)
    • libm(數學庫)
    • libOpenMAXAL.so(OpenMAX AL 1.0.1 支援)
    • libOpenSLES.so(OpenSL ES 1.0.1 音訊支援)
    • libRS.so
    • libstdc++(對 C++ 的最低支援)
    • libvulkan.so(Vulkan)
    • libz(Zlib 壓縮)
    • JNI介面
  • [C-0-8] 不得新增或刪除上面列出的本機庫的公共函數。

  • [C-0-9]必須列出其他直接暴露於/vendor/etc/public.libraries.txt中的第三方應用程式的非AOSP程式庫。
  • [C-0-10] 不得將在 AOSP 中作為系統函式庫實作和提供的任何其他本機函式庫暴露給面向 API 等級 24 或更高等級的第三方應用,因為它們是保留的。
  • [C-0-11]必須透過libGLESv3.so函式庫匯出所有OpenGL ES 3.1和Android擴充包函數符號。請注意,儘管必須存在所有符號,但第7.1.4.1節更詳細地描述了何時預期每個相應功能的完整實現的要求。
  • [C-0-12] MUST export function symbols for the core Vulkan 1.0 function symobls, as well as the VK_KHR_surface , VK_KHR_android_surface , VK_KHR_swapchain , VK_KHR_maintenance1 , and VK_KHR_get_physical_device_properties2 extensions through the libvulkan.so library.請注意,儘管必須存在所有符號,但第7.1.4.2節更詳細地描述了何時預期每個相應功能的完整實現的要求。
  • 應使用上游 Android 開源專案中提供的源代碼和頭文件進行構建

請注意,Android NDK 的未來版本可能會引入對其他 ABI 的支援。

3.3.2. 32位元ARM本地程式碼相容性

如果設備實作是64位元ARM設備,則:

  • [C-1-1]儘管ARMV8體系結構棄用了多個CPU操作,包括現有本機程式碼中使用的某些操作,但必須透過本機CPU支援或透過軟體模擬可用於32位元本機ARM程式碼的以下棄用操作:

    • SWP和SWPB說明
    • 設定指令
    • CP15ISB,CP15DSB和CP15DMB屏障操作

如果設備實作包括32位元ARM ABI,則它們:

  • [C-2-1]在32位元ARM應用程式讀取時,必須在/proc/cpuinfo中包含以下行,以確保與使用Android NDK的舊版建立的應用程式相容。

    • Features: ,然後是該裝置支援的任何選用ARMV7 CPU功能的清單。
    • CPU architecture:接著是描述設備最高支撐的ARM架構的整數(例如,對於ARMV8設備,「 8」)。
  • 透過64位元ARM或非ARM應用程式閱讀時,不應更改/proc/cpuinfo

3.4.網路相容性

3.4.1.網頁視圖相容性

如果裝置實作提供了android.webkit.Webview API的完整實現,則它們:

  • [C-1-1]必須報告android.software.webview
  • [C-1-2]必須使用Android 8.0分支的上游Android開源專案的Chromium Project構建,以實現android.webkit.WebView API。
  • [C-1-3] WebView報告的用戶代理字串必須以這種格式:

    Mozilla/5.0(Linux; Android $(版本); $(型號)build/$(build); wv)AppleWebkit/537.36(Khtml,像Gecko)版本/4.0 $(Chromium_ver)Mobile Safari/537.36

    • $(VERSION) 字串的值必須與 android.os.Build.VERSION.RELEASE 的值相同。
    • $(MODEL) 字串的值必須與 android.os.Build.MODEL 的值相同。
    • $(BUILD) 字串的值必須與 android.os.Build.ID 的值相同。
    • $(CHROMIUM_VER) 字串的值必須是上游 Android 開源專案中 Chromium 的版本。
    • 設備實作可以在用戶代理字串中省略 Mobile。
  • WebView 元件應該包含對盡可能多的 HTML5 功能的支持,並且如果它支援該功能,則應該符合HTML5 規範

3.4.2.瀏覽器相容性

如果設備實作包括用於一般 Web 瀏覽的獨立瀏覽器應用程序,則它們:

  • [C-1-1] 必須支援與 HTML5 關聯的每個 API:
  • [C-1-2]必須支援HTML5/W3C WebStorage API ,並應支援HTML5/W3C索引DB API 。請注意,隨著 Web 開發標準機構逐漸轉向支援 IndexedDB 而不是 Webstorage,IndexedDB 預計將成為 Android 未來版本中的必要組件。
  • 可以在獨立的瀏覽器應用程式中提供自訂使用者代理字串。
  • 應在獨立瀏覽器應用程式上實施對HTML5盡可能多的支援(無論是基於上游WebKit瀏覽器應用程式還是第三方替代)。

但是,如果設備實作不包括獨立瀏覽器應用程序,則它們:

3.5. API 行為相容性

每個 API 類型(託管、軟體、本機和 Web)的行為必須與上游Android 開源專案的首選實作一致。一些特定的兼容性領域是:

  • [C-0-1]設備不得改變標準意圖的行為或語意。
  • [C-0-2] 設備不得更改特定類型的系統元件(例如服務、活動、ContentProvider 等)的生命週期或生命週期語意。
  • [C-0-3] 設備不得更改標準權限的語意。
  • 設備不得改變背景應用程式上強制執行的限制。更具體地說,對於背景應用程式:
    • [C-0-4]他們必須停止執行該應用程式註冊的回調,以從GnssMeasurementGnssNavigationMessage接收輸出。
    • [C-0-5]他們必須透過LocationManager API類別或WifiManager.startScan()方法對應用程式提供的更新頻率進行評分。
    • [C-0-6]如果該應用程式針對API等級25或更高,則它們不得允許在應用程式清單中為標準Android意圖的隱式廣播註冊廣播接收器,除非廣播意圖需要"signature""signatureOrSystem" protectionLevel許可或在豁免清單中。
    • [C-0-7]如果該應用程式針對API等級25或更高,則必須停止應用程式的背景服務,就像該應用程式稱為stopSelf()方法一樣,除非將應用程式放置在臨時允許清單上處理使用者可見的任務。
    • [C-0-8] 如果套用的目標 API 等級為 25 或更高,則它們必須釋放應用程式所持有的喚醒鎖定。

上面的列表並不全面。相容性測試套件 (CTS) 測試平台的重要部分(但不是全部)的行為相容性。實作者有責任確保與 Android 開源專案的行為相容性。因此,裝置實現者應該盡可能使用透過 Android 開源專案提供的原始程式碼,而不是重新實作系統的重要部分。

3.6. API命名空間

Android 遵循 Java 程式語言定義的套件和類別命名空間約定。為了確保與第三方應用程式的相容性,裝置實作者不得對這些套件命名空間進行任何禁止的修改(見下文):

  • java.*
  • javax.*
  • sun.*
  • android.*
  • com.android.*

也就是說,他們:

  • [C-0-1] 不得透過更改任何方法或類別簽名,或刪除類別或類別欄位來修改 Android 平台上公開公開的 API。
  • [C-0-2]不得將任何公開暴露的元素(例如類,接口,字段或方法)或現有類或接口的字段或方法)或測試或系統API添加到上述名稱空間中的API中。 「公開暴露的元素」是任何未用上游Android原始碼中使用的「 @Hide」標記裝飾的構造。

設備實施者可以修改API的基本實現,但進行了修改:

  • [C-0-3] 不得影響任何公開公開的 API 的規定行為和 Java 語言簽章。
  • [C-0-4]不得向開發人員做廣告或以其他方式接觸。

但是,裝置實作者可以在標準Android名稱空間之外新增自訂API,但自訂API:

  • [C-0-5] 不得位於由其他組織擁有或引用其他組織的命名空間。例如,裝置實作者不得將 API 新增至com.google.*或類似的命名空間:只有 Google 可以做到。同樣,Google 不得將 API 新增至其他公司的命名空間。
  • [C-0-6]必須在Android共享庫中打包,以便只有明確使用它們的應用程式(透過<susta-library>機制)受到此類API的記憶體使用的增加影響。

如果設備實現者建議改進上述包命名空間之一(例如透過向現有 API 添加有用的新功能,或添加新 API),則實現者應該訪問source.android.com並開始貢獻更改和的過程代碼,根據該網站上的信息。

請注意,上述限制對應於 Java 程式語言中命名 API 的標準約定;本節的目的只是為了加強這些約定,並透過將其納入此相容性定義來使其具有約束力。

3.7.運行時相容性

設備實現:

  • [C-0-1] 必須支援完整的 Dalvik 執行檔 (DEX) 格式以及Dalvik 字節碼規格和語意

  • [C-0-2]必須配置Dalvik Runtimes,以根據上游Android平台分配內存,並按照下表指定。 (有關螢幕尺寸和螢幕密度定義,請參閱第 7.1.1 節。)

  • 應使用Android Runtime(ART),DALVIK可執行格式的參考上游實作以及參考實作的軟體包管理系統。

  • 應在各種執行模式和目標架構下執行模糊測試,以確保運行時的穩定性。請參閱 Android 開源專案網站中的JFuzzDexFuzz

請注意,下面指定的記憶體值被視為最小值,設備實作可以為每個應用程式分配更多記憶體。

螢幕佈局螢幕密度最小應用記憶體
Android手錶120 dpi(LDPI) 32MB
160 dpi (mdpi)
213 dpi(電視dpi)
240 dpi(高清) 36MB
280dpi (280dpi)
320 dpi(xhdpi) 48MB
360dpi (360dpi)
400dpi (400dpi) 56MB
420 dpi (420dpi) 64MB
480 dpi (xxhdpi) 88MB
560dpi(560dpi) 112MB
640 dpi (xxxhdpi) 154MB
小/正常120 dpi(LDPI) 32MB
160 dpi (mdpi)
213 dpi(電視dpi) 48MB
240 dpi(高清)
280dpi (280dpi)
320 dpi(xhdpi) 80MB
360dpi (360dpi)
400dpi (400dpi) 96MB
420 dpi (420dpi) 112MB
480 dpi (xxhdpi) 128MB
560dpi(560dpi) 192MB
640 dpi (xxxhdpi) 256MB
大的120 dpi(LDPI) 32MB
160 dpi (mdpi) 48MB
213 dpi(電視dpi) 80MB
240 dpi(高清)
280dpi (280dpi) 96MB
320 dpi(xhdpi) 128MB
360dpi (360dpi) 160MB
400dpi (400dpi) 192MB
420 dpi (420dpi) 228MB
480 dpi (xxhdpi) 256MB
560dpi(560dpi) 384MB
640 dpi (xxxhdpi) 512MB
超大120 dpi(LDPI) 48MB
160 dpi (mdpi) 80MB
213 dpi(電視dpi) 96MB
240 dpi(高清)
280dpi (280dpi) 144MB
320 dpi(xhdpi) 192MB
360dpi (360dpi) 240MB
400dpi (400dpi) 288MB
420 dpi (420dpi) 336MB
480 dpi (xxhdpi) 384MB
560dpi(560dpi) 576MB
640 dpi (xxxhdpi) 768MB

3.8.使用者介面相容性

3.8.1.啟動器(主螢幕)

Android 包括啟動器應用程式(主畫面)並支援第三方應用程式來取代裝置啟動器(主畫面)。

如果設備實現允許第三方應用程式替換設備主螢幕,則它們:

  • [C-1-1]必須聲明平台功能android.software.home_screen
  • [C-1-2]當第三方應用程式使用<adaptive-icon>標籤提供其圖示時,必須返回AdaptiveIconDrawable對象,並且呼叫了檢索圖示的PackageManager方法。

如果裝置實作包括支援快捷方式內應用程式固定的預設啟動器,則它們:

相反,如果設備實作不支援應用程式內固定,則它們:

如果裝置實作實作了預設啟動器,可透過ShortcutManager API 快速存取第三方應用程式提供的其他捷徑,則:

  • [C-4-1]必須支援所有已記錄的快捷方式(例如靜態和動態快捷方式,固定快捷方式),並完全實現ShortcutManager API類的API。

如果裝置實作包括一個顯示應用程式圖示徽章的預設啟動器應用程序,則它們:

  • [C-5-1]必須尊重NotificationChannel.setShowBadge() API方法。換句話說,如果該值設為true ,則顯示與應用程式圖示相關的視覺負擔性,並且當所有應用程式的通知頻道都將值設為false時,請勿顯示任何應用圖示徽章方案。
  • 當第三方應用程式透過使用專有API表示支援專有徽章方案時,可以使用專有徽章方案覆蓋應用程式圖示徽章,但應使用SDK中描述的通知徽章API所提供的資源和價值觀,例如Notification.Builder.setNumber()Notification.Builder.setBadgeIconType() API。

3.8.2.小部件

Android透過定義元件類型以及對應的API和生命週期來支援第三方應用程式小工具,該小工具允許應用程式向最終用戶公開「 AppWidget」

如果設備實作支援第三方應用程式小部件,則它們:

  • [C-1-1]必須聲明對平台功能android.software.app_widgets的支援。
  • [C-1-2]必須包括對AppWidgets的內建支持,並將使用者介面提供直接在啟動器中直接添加,配置,查看和刪除AppWidgets的服務。
  • [C-1-3]必須能夠在標準網格大小中渲染4 x 4的小部件。有關詳細信息,請參見Android SDK文件中的應用程式小工具設計指南
  • 可以支援鎖定螢幕上的應用程式小工具。

如果裝置實作支援第三方應用程式小工具和應用程式內固定快捷方式,則它們:

3.8.3.通知

Android包括NotificationNotificationManager API,允許第三方應用程式開發人員使用硬體元件(例如聲音,振動和光線)和軟體功能(例如通知陰影,系統列)通知用戶著名事件,並吸引用戶的注意。

3.8.3.1。通知的呈現

如果設備實現允許第三方應用程式通知用戶著名事件,則他們:

  • [C-1-1]必須支援使用硬體功能的通知,如SDK文件中所述,並在設備實現硬體的範圍內。例如,如果裝置實作包含振動器,則它必須正確實作振動 API。如果設備實作缺少硬件,則對應的 API 必須實作為無操作。此行為在第 7 節中有進一步詳細介紹。
  • [C-1-2]必須正確渲染API中提供的所有資源(圖標,動畫文件等),或在狀態/系統欄圖標樣式指南中,儘管它們可以為通知提供替代的用戶體驗通過參考Android開源實現。
  • [C-1-3]必須尊重並正確實施API所描述的行為,以更新,刪除和群組通知。
  • [C-1-4]必須提供SDK中記錄的NotificationChannel API的全部行為。
  • [C-1-5]必須提供使用者負擔能力,以阻止和修改每個頻道和應用程式包層級的某個第三方應用程式的通知。
  • [C-1-6]也必須提供使用者負擔來顯示已刪除的通知管道。
  • 應該支援豐富的通知。
  • 作為主題通知,應提出一些更高的優先通知。
  • 應該有使用者負擔能力貪睡通知。
  • 只能管理第三方應用程式何時能夠通知用戶著名事件的可見性和時機,以減輕諸如駕駛員分心之類的安全問題。

如果設備實現支援豐富的通知,則它們:

  • [C-2-1]必須使用Notification.Style類別提供的確切資源及其用於提出的資源元素的子類別。
  • 應介紹通知中定義的每個資源元素(例如圖標,標題和摘要文字)。 Notification.Style API類別及其子類別。

如果設備實現支援主題通知:它們:

  • [C-3-1]必須按照通知中所述的主題通知視圖和資源。 Notification.Builder API類別何時提出通知。
3.8.3.2。通知聽眾服務

Android包括允許應用程式(一旦用戶明確啟用了)的NotificationListenerService API,可以在發布或更新時接收所有通知的副本。

設備實現:

  • [C-0-1]必須正確且迅速地將通知完整地更新為所有此類安裝和使用者啟用的偵聽器服務,包括附加到Notification物件的所有元資料。
  • [C-0-2]必須尊重snoozeNotification() API調用,並駁回通知並在API呼叫中設定的貪睡持續時間後進行回調。

如果設備實現具有snooze通知的使用者負擔,則它們:

  • [C-1-1]必須透過標準API(例如NotificationListenerService.getSnoozedNotifications()正確地反映了通知狀態。
  • [C-1-2]必須使此用戶負擔能力可用於從每個安裝的第三方應用程式中的貪睡通知,除非它們來自持久/前景服務。
3.8.3.3。 DND(請勿打擾)

如果設備實現支援DND功能,則它們:

  • [C-1-1]必須實施一項將回應意圖action_notification_policy_access_settings的活動,該活動對於使用UI_MODE_TYPE_NORMAL實現,它必須是一項活動,使用者可以授予或拒絕應用程式存取DND策略配置的活動。
  • [C-1-2]必須,對於設備實施提供了一種手段,用戶可以授予或拒絕第三方應用程式訪問DND策略配置時,請顯示由應用程式與用戶創建的應用程式創建的自動DND規則-定義規則。
  • [C-1-3]必須遵守沿著NotificationManager.Policy suppressedVisualEffects值,並且如果應用程式設定了任何dustresse_effect_screen_off或dustrese_effect_screen_on標誌,則應向使用者表明在DND設定選單中抑制視覺效果。

Android包含API,使開發人員可以將搜尋納入其應用程式中,並將其應用程式的資料曝光到全球系統搜尋。一般來說,此功能由單一系統範圍的使用者介面組成,允許使用者輸入查詢、在使用者鍵入時顯示建議並顯示結果。 Android API允許開發人員重複使用此介面以在自己的應用程式中提供搜索,並允許開發人員為常見的全域搜尋使用者介面提供結果。

  • Android 裝置實作應該包括全域搜索,這是一個單一的、共享的、系統範圍的搜尋使用者介面,能夠響應用戶輸入提供即時建議。

如果設備實現實現了全域搜尋接口,則它們:

  • [C-1-1]必須實作允許第三方應用程式以全域搜尋模式運行時將建議新增至搜尋框的API。

如果沒有安裝使用全域搜尋的第三方應用程式:

  • 預設行為應該是顯示Web搜尋引擎結果和建議。

Android還包括輔助API ,以允許應用程式選擇與裝置上的助理共享目前上下文的多少資訊。

如果設備實施支援輔助行動,則他們:

  • [C-2-1]當上下文共享時,必須清楚地向最終用戶表示:
    • 每次輔助應用程式存取上下文時,都會在螢幕邊緣周圍顯示符合或超過Android開源專案實現的持續時間和亮度的白光。
    • 對於預先安裝的輔助應用程序,從預設的語音輸入和助手應用程式設定選單範圍內提供少於兩個導航的用戶負擔,並且僅在用戶透過熱門或輔助導航金鑰輸入來明確調用輔助應用程式時共享上下文。
  • [C-2-2]依照第7.2.3節所述啟動輔助應用程式的指定互動必須啟動使用者選擇的輔助應用程序,換句話說,實作VoiceInteractionService的應用程式或處理ACTION_ASSIST意圖的活動。
  • [C-SR] STRONGLY RECOMMENDED to use long press on HOME key as this designated interaction.

3.8.5。 Alerts and Toasts

Applications can use the Toast API to display short non-modal strings to the end user that disappear after a brief period of time, and use the TYPE_APPLICATION_OVERLAY window type API to display alert windows as an overlay over other apps.

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] MUST provide a user affordance to block an app from displaying alert windows that use the TYPE_APPLICATION_OVERLAY . The AOSP implementation meets this requirement by having controls in the notification shade.

  • [C-1-2] 必須遵守 Toast API,並以某種高度可見的方式從應用程式向最終用戶顯示 Toast。

3.8.6。主題

Android provides “themes” as a mechanism for applications to apply styles across an entire Activity or application.

Android 包含「Holo」和「Material」主題系列作為一組定義的樣式,供應用程式開發人員在想要匹配 Android SDK 定義的Holo 主題外觀和感覺時使用。

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] 不得更改向應用程式公開的任何Holo 主題屬性
  • [C-1-2] MUST support the “Material” theme family and MUST NOT alter any of the Material theme attributes or their assets exposed to applications.

Android also includes a “Device Default” theme family as a set of defined styles for application developers to use if they want to match the look and feel of the device theme as defined by the device implementer.

Android supports a variant theme with translucent system bars, which allows application developers to fill the area behind the status and navigation bar with their app content.為了在此配置中實現一致的開發人員體驗,在不同的裝置實作中保持狀態列圖示樣式非常重要。

If device implementations include a system status bar, they:

  • [C-2-1] MUST use white for system status icons (such as signal strength and battery level) and notifications issued by the system, unless the icon is indicating a problematic status or an app requests a unless the icon is indicating a problematic status or an app requests a unless 保險。
  • [C-2-2] Android device implementations MUST change the color of the system status icons to black (for details, refer to R.style ) when an app requests a light status bar.

3.8.7.動態壁紙

Android 定義了一種元件類型以及相應的 API 和生命週期,允許應用程式向最終用戶公開一個或多個「動態桌布」 。動態壁紙是動畫、圖案或具有有限輸入功能的類似圖像,在其他應用程式後面顯示為壁紙。

如果硬體能夠以合理的幀速率運行所有動態壁紙,且沒有功能限制,並且不會對其他應用程式產生不利影響,則該硬體被認為能夠可靠地運行動態壁紙。如果硬體限制導致壁紙和/或應用程式崩潰、故障、消耗過多的 CPU 或電池電量,或以不可接受的低幀速率運行,則該硬體被視為無法運行動態壁紙。例如,某些動態桌布可能使用 OpenGL 2.0 或 3.x 上下文來渲染其內容。動態桌布將無法在不支援多個 OpenGL 上下文的硬體上可靠地運行,因為使用 OpenGL 上下文的動態桌布可能會與也使用 OpenGL 上下文的其他應用程式發生衝突。

  • 如上所述,能夠可靠地運行動態壁紙的設備實現應該實現動態壁紙。

如果設備實現實現了動態壁紙,那麼它們:

  • [C-1-1] MUST report the platform feature flag android.software.live_wallpaper.

3.8.8.活動切換

The upstream Android source code includes the overview screen , a system-level user interface for task switching and displaying recently accessed activities and tasks using a thumbnail image of the application's graphical state at the moment the user last left the application.

Device implementations including the recents function navigation key as detailed in section 7.2.3 MAY alter the interface.

If device implementations including the recents function navigation key as detailed in section 7.2.3 alter the interface, they:

  • [C-1-1] MUST support at least up to 20 displayed activities.
  • SHOULD at least display the title of 4 activities at a time.
  • [C-1-2] 必須實現螢幕固定行為,並提供使用者用於切換該功能的設定選單。
  • 應顯示最近的突出顯示顏色、圖示、螢幕標題。
  • SHOULD display a closing affordance ("x") but MAY delay this until user interacts with screens.
  • SHOULD implement a shortcut to switch easily to the previous activity
  • SHOULD trigger the fast-switch action between the two most recently used apps, when the recents function key is tapped twice.
  • SHOULD trigger the split-screen multiwindow-mode, if supported, when the recents functions key is long pressed.
  • 可以將關聯的最近內容顯示為一起移動的群組。

  • [C-SR] Device implementations are STRONGLY RECOMMENDED to use the upstream Android user interface (or a similar thumbnail-based interface) for the overview screen.

3.8.9。輸入管理

Android includes support for Input Management and support for third-party input method editors.

If device implementations allow users to use third-party input methods on the device, they:

  • [C-1-1] 必須聲明平台功能 android.software.input_methods 並支援 Android SDK 文件中定義的 IME API。
  • [C-1-2] MUST provide a user-accessible mechanism to add and configure third-party input methods in response to the android.settings.INPUT_METHOD_SETTINGS intent.

If device implementations declare the android.software.autofill feature flag, they:

3.8.10.鎖定螢幕媒體控制

The Remote Control Client API is deprecated from Android 5.0 in favor of the Media Notification Template that allows media applications to integrate with playback controls that are displayed on the lock screen.

3.8.11. Screen savers (previously Dreams)

Android includes support for interactivescreensavers , previously referred to as Dreams. Screen savers allow users to interact with applications when a device connected to a power source is idle or docked in a desk dock. Android Watch devices MAY implement screen savers, but other types of device implementations SHOULD include support for screen savers and provide a settings option for users toconfigure screen savers in response to the android.settings.DREAM_SETTINGS intent.

3.8.12.地點

If device implementations include a hardware sensor (eg GPS) that is capable of providing the location coordinates:

  • [C-1-1] location modes MUST be displayed in the Location menu within Settings.

3.8.13.統一碼和字體

Android includes support for the emoji characters defined in Unicode 10.0 .

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] MUST be capable of rendering these emoji characters in color glyph.
  • [C-1-2] 必須支援:
    • Roboto 2 font with different weights—sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black, sans-serif-condensed, sans-serif-condensed-light for the languages available on the裝置.
    • Full Unicode 7.0 coverage of Latin, Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and all glyphs in the currency symbols block of Unicode 7.0.
  • 應支持Unicode 技術報告 #51中指定的膚色和多樣化的家庭表情符號。

If device implementations include an IME, they:

  • SHOULD provide an input method to the user for these emoji characters.

3.8.14. Multi-windows

If device implementations have the capability to display multiple activities at the same time, they:

  • [C-1-1] MUST implement such multi-window mode(s) in accordance with the application behaviors and APIs described in the Android SDK multi-window mode support documentation and meet the following requirements:
  • [C-1-2] Applications can indicate whether they are capable of operating in multi-window mode in the AndroidManifest.xml file, either explicitly via setting the android:resizeableActivity attribute to true or implicitly by having the targetSdkVersion > 24. Apps that explicitly set this attribute to false in their manifest MUST NOT be launched in multi-window mode. Older apps with targetSdkVersion < 24 that did not set this android:resizeableActivity attribute MAY be launched in multi-window mode, but the system MUST provide warning that the app may not work as expected in multi-window mode.
  • [C-1-3] MUST NOT offer split-screen or freeform mode if the screen height < 440 dp and the screen width < 440 dp.
  • Device implementations with screen size xlarge SHOULD support freeform mode.

如果設備實現支援多視窗模式和分割螢幕模式,則它們:

  • [C-2-1] MUST preload a resizeable launcher as the default.
  • [C-2-2] MUST crop the docked activity of a split-screen multi-window but SHOULD show some content of it, if the Launcher app is the focused window.
  • [C-2-3] MUST honor the declared AndroidManifestLayout_minWidth and AndroidManifestLayout_minHeight values of the third-party launcher application and not override these values in the course of showing some content of the docked activity.

If device implementations support multi-window mode(s) and picture-in-picture multi-window mode, they:

  • [C-3-1] MUST launch activities in picture-in-picture multi-window mode when the app is: * Targeting API level 26 or higher and declares android:supportsPictureInPicture * Targeting API level 25 or lower and declares both android:resizeableActivity and android:supportsPictureInPicture .
  • [C-3-2] MUST expose the actions in their SystemUI as specified by the current PIP activity through the setActions() API.
  • [C-3-3] MUST support aspect ratios greater than or equal to 1:2.39 and less than or equal to 2.39:1, as specified by the PIP activity through the setAspectRatio() API.
  • [C-3-4] MUST use KeyEvent.KEYCODE_WINDOW to control the PIP window; if PIP mode is not implemented, the key MUST be available to the foreground activity.
  • [C-3-5] MUST provide a user affordance to block an app from displaying in PIP mode; the AOSP implementation meets this requirement by having controls in the notification shade.
  • [C-3-6] MUST allocate minimum width and height of 108 dp for the PIP window and minimum width of 240 dp and height of 135 dp for the PIP window when the Configuration.uiMode is configured as UI_MODE_TYPE_TELEVISION

3.9.設備管理

Android includes features that allow security-aware applications to perform device administration functions at the system level, such as enforcing password policies or performing remote wipe, through the Android Device Administration API ].

If device implementations implement the full range of device administration policies defined in the Android SDK documentation, they:

  • [C-1-1] MUST declare android.software.device_admin .
  • [C-1-2] MUST support device owner provisioning as described in section 3.9.1 and section 3.9.1.1 .
  • [C-1-3] MUST declare the support of manged profiles via the android.software.managed_users feature flag, except for when the device is configured so that it would report itself as a low RAM device or so that it allocate internal (non-removable) storage as shared storage.

3.9.1 Device Provisioning

3.9.1.1 Device owner provisioning

If device implementations declare android.software.device_admin , they:

If device implementations declare android.software.device_admin , but also include a proprietary Device Owner management solution and provide a mechanism to promote an application configured in their solution as a "Device Owner equivalent" to the standard "Device Owner" as recognized by the standard Android DevicePolicyManager APIs, they:

  • [C-2-1] MUST have a process in place to verify that the specific app being promoted belongs to a legitimate enterprise device management solution and it has been already configured in the proprietary solution to have the right equist" 。
  • [C-2-2] MUST show the same AOSP Device Owner consent disclosure as the flow initiated by android.app.action.PROVISION_MANAGED_DEVICE prior to enrolling the DPC application as "Device Owner".
  • MAY have user data on the device prior to enrolling the DPC application as "Device Owner".
3.9.1.2 Managed profile provisioning

If device implementations declare android.software.managed_users , they:

  • [C-1-1] MUST implement the APIs allowing a Device Policy Controller (DPC) application to become the owner of a new Managed Profile .

  • [C-1-2] The managed profile provisioning process (the flow initiated by android.app.action.PROVISION_MANAGED_PROFILE ) users experience MUST align with the AOSP implementation.

  • [C-1-3] MUST provide the following user affordances within the Settings to indicate to the user when a particular system function has been disabled by the Device Policy Controller (DPC):

    • A consistent icon or other user affordance (for example the upstream AOSP info icon) to represent when a particular setting is restricted by a Device Admin.
    • A short explanation message, as provided by the Device Admin via the setShortSupportMessage .
    • The DPC application's icon.

3.9.2 Managed Profile Support

If device implementations declare android.software.managed_users , they:

  • [C-1-1] MUST support managed profiles via the android.app.admin.DevicePolicyManager APIs.
  • [C-1-2] MUST allow one and only one managed profile to be created .
  • [C-1-3] MUST use an icon badge (similar to the AOSP upstream work badge) to represent the managed applications and widgets and other badged UI elements like Recents & Notifications.
  • [C-1-4] MUST display a notification icon (similar to the AOSP upstream work badge) to indicate when user is within a managed profile application.
  • [C-1-5] MUST display a toast indicating that the user is in the managed profile if and when the device wakes up (ACTION_USER_PRESENT) and the foreground application is within the managed profile.
  • [C-1-6] Where a managed profile exists, MUST show a visual affordance in the Intent 'Chooser' to allow the user to forward the intent from the managed profile to the primary user or vice versa, if enable Polid by the Device or vice versa, if enable Polid by the Device or vice versa, if enable Poli控制器。
  • [C-1-7] Where a managed profile exists, MUST expose the following user affordances for both the primary user and the managed profile:
    • Separate accounting for battery, location, mobile data and storage usage for the primary user and managed profile.
    • Independent management of VPN Applications installed within the primary user or managed profile.
    • Independent management of applications installed within the primary user or managed profile.
    • Independent management of accounts within the primary user or managed profile.
  • [C-1-8] MUST ensure the preinstalled dialer, contacts and messaging applications can search for and look up caller information from the managed profile (if one exists) alongside those from the primary profile, if the Device Policy Controller permits it.
  • [C-1-9] MUST ensure that it satisfies all the security requirements applicable for a device with multiple users enabled (see section 9.5 ), even though the managed profile is not counted as another user in addition to the primary user.
  • [C-1-10] MUST support the ability to specify a separate lock screen meeting the following requirements to grant access to apps running in a managed profile.
  • When contacts from the managed profile are displayed in the preinstalled call log, in-call UI, in-progress and missed-call notifications, contacts and messaging apps they SHOULD be badged with the same badge used to indicate managed profile applications.

3.10.無障礙

Android 提供了一個輔助功能層,可幫助殘障用戶更輕鬆地導航其裝置。此外,Android 還提供平台 API,使輔助功能服務實現能夠接收使用者和系統事件的回調,並產生備用回饋機制,例如文字轉語音、觸覺回饋和軌跡球/方向鍵導航。

If device implementations support third-party accessibility services, they:

  • [C-1-1] 必須提供 Android 輔助功能框架的實現,如輔助功能 API SDK 文件中所述。
  • [C-1-2] MUST generate accessibility events and deliver the appropriate AccessibilityEvent to all registered AccessibilityService implementations as documented in the SDK.
  • [C-1-3] MUST honor the android.settings.ACCESSIBILITY_SETTINGS intent to provide a user-accessible mechanism to enable and disable the third-party accessibility services alongside the preloaded accessibility services.
  • [C-1-4] MUST add a button in the system's navigation bar allowing the user to control the accessibility service when the enabled accessibility services declare the AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON . Note that for device implementations with no system navigation bar, this requirement is not applicable, but device implementations SHOULD provide a user affordance to control these accessibility services.

If device implementations include preloaded accessibility services, they:

  • [C-2-1] MUST implement these preloaded accessibility services as Direct Boot Aware apps when the data storage is encrypted with File Based Encryption (FBE).
  • 應在開箱即用的設定流程中為使用者提供一種機制,以啟用相關的輔助功能服務,以及調整字體大小、顯示大小和放大手勢的選項。

3.11.文字轉語音

Android includes APIs that allow applications to make use of text-to-speech (TTS) services and allows service providers to provide implementations of TTS services.

如果裝置實作報告了 android.hardware.audio.output 功能,則:

如果設備實現支援安裝第三方 TTS 引擎,則:

  • [C-2-1] MUST provide user affordance to allow the user to select a TTS engine for use at system level.

3.12.電視輸入框架

Android Television 輸入框架 (TIF)簡化了向 Android Television 裝置交付即時內容的過程。 TIF 提供標準 API 來建立控制 Android Television 裝置的輸入模組。

If device implementations support TIF, they:

  • [C-1-1] MUST declare the platform feature android.software.live_tv .
  • [C-1-2] MUST preload a TV application (TV App) and meet all requirements described in section 3.12.1 .

3.12.1.電視應用程式

If device implementations support TIF:

  • [C-1-1] The TV App MUST provide facilities to install and use TV Channels and meet the following requirements.

The TV app that is required for Android device implementations declaring the android.software.live_tv feature flag, MUST meet the following requirements:

  • Device implementations SHOULD allow third-party TIF-based inputs ( third-party inputs ) to be installed and managed.
  • Device implementations MAY provide visual separation between pre-installed TIF-based inputs (installed inputs) and third-party inputs.
  • Device implementations SHOULD NOT display the third-party inputs more than a single navigation action away from the TV App (ie expanding a list of third-party inputs from the TV App).

The Android Open Source Project provides an implementation of the TV App that meets the above requirements.

3.12.1.1. Electronic Program Guide

If device implementations support TIF, they:

  • [C-1-1] MUST show an informational and interactive overlay, which MUST include an electronic program guide (EPG) generated from the values in the TvContract.Programs fields.
  • [C-1-2] On channel change, device implementations MUST display EPG data for the currently playing program.
  • [SR] The EPG is STRONGLY RECOMMENDED to display installed inputs and third-party inputs with equal prominence. The EPG SHOULD NOT display the third-party inputs more than a single navigation action away from the installed inputs on the EPG.
  • The EPG SHOULD display information from all installed inputs and third-party inputs.
  • The EPG MAY provide visual separation between the installed inputs and third-party inputs.
3.12.1.2.導航

If device implementations support TIF, they:

  • [C-1-1] MUST allow navigation for the following functions via the D-pad, Back, and Home keys on the Android Television device's input device(s) (ie remote control, remote control application, or game controller):

    • Changing TV channels
    • Opening EPG
    • Configuring and tuning to third-party TIF-based inputs
    • Opening Settings menu
  • SHOULD pass key events to HDMI inputs through CEC.

3.12.1.3. TV input app linking

If device implementations support TIF:

  • [C-1-1] Android Television device implementations MUST support TV input app linking , which allows all inputs to provide activity links from the current activity to another activity (ie a link from live programming to related content).
  • [C-1-2] The TV App MUST show TV input app linking when it is provided.
3.12.1.4.時移

If device implementations support TIF, they:

  • [SR] STRONGLY RECOMMENDED to support time shifting, which allows the user to pause and resume live content.
  • SHOULD provide the user a way to pause and resume the currently playing program, if time shifting for that program is available .
3.12.1.5. TV recording

If device implementations support TIF, they:

  • [SR] STRONGLY RECOMMENDED to support TV recording.
  • SHOULD provide a user interface to play recorded programs.
  • If the TV input supports recording and the recording of a program is not prohibited , the EPG MAY provide a way to record a program .

3.13.快速設定

Android 提供了快速設定 UI 元件,允許快速存取常用或緊急需要的操作。

If device implementations include a Quick Settings UI component, they:

  • [C-1-1] MUST allow the user to add or remove the tiles provided through the quicksettings APIs from a third-party app.
  • [C-1-2] 不得自動將第三方應用程式中的圖塊直接直接加入「快速設定」。
  • [C-1-3] 必須在系統提供的快速設定圖塊旁顯示所有使用者從第三方應用程式新增的圖塊。

3.14。 Media UI

If device implementations include the UI framework that supports third-party apps that depend on MediaBrowser and MediaSession , they:

  • [C-1-1] MUST display MediaItem icons and notification icons unaltered.
  • [C-1-2] MUST display those items as described by MediaSession, eg, metadata, icons, imagery.
  • [C-1-3] MUST show app title.
  • [C-1-4] MUST have drawer to present MediaBrowser hierarchy.

3.15。 Instant Apps

Device implementations MUST satisfy the following requirements:

  • [C-0-1] Instant Apps MUST only be granted permissions that have the android:protectionLevel set to "ephemeral" .
  • [C-0-2] Instant Apps MUST NOT interact with installed apps via implicit intents unless one of the following is true:
    • 組件的意圖模式過濾器已公開並具有 CATEGORY_BROWSABLE
    • The action is one of ACTION_SEND, ACTION_SENDTO, ACTION_SEND_MULTIPLE
    • 目標透過android:visibleToInstantApps明確公開
  • [C-0-3] Instant Apps MUST NOT interact explicitly with installed apps unless the component is exposed via android:visibleToInstantApps.
  • [C-0-4] IInstalled Apps MUST NOT see details about Instant Apps on the device unless the Instant App explicitly connects to the installed application.

3.16。 Companion Device Pairing

Android includes support for companion device pairing to more effectively manage association with companion devices and provides the CompanionDeviceManager API for apps to access this feature.

如果設備實現支援配套設備配對功能,則:

  • [C-1-1] MUST declare the feature flag FEATURE_COMPANION_DEVICE_SETUP .
  • [C-1-2] MUST ensure the APIs in the android.companion package is fully implemented.
  • [C-1-3] MUST provide user affordances for the user to select/confirm a companion device is present and operational.

4. 應用程式封裝相容性

Devices implementations:

  • [C-0-1] MUST be capable of installing and running Android “.apk” files as generated by the “aapt” tool included in the official Android SDK .
  • As the above requirement may be challenging, device implementations are RECOMMENDED to use the AOSP reference implementation's package management systemDevice implementations.
  • [C-0-2] MUST support verifying “.apk” files using the APK Signature Scheme v2 and JAR signing .
  • [C-0-3] MUST NOT extend either the .apk , Android Manifest , Dalvik bytecode , or RenderScript bytecode formats in such a way that would prevent those files from installing and running correctly on other compatible devices.
  • [C-0-4] MUST NOT allow apps other than the current "installer of record" for the package to silently uninstall the app without any prompt, as documented in the SDK for the DELETE_PACKAGE permission. The only exceptions are the system package verifier app handling PACKAGE_NEEDS_VERIFICATION intent and the storage manager app handling ACTION_MANAGE_STORAGE intent.

  • [C-0-5] MUST have an activity that handles the android.settings.MANAGE_UNKNOWN_APP_SOURCES intent.

  • [C-0-6] MUST NOT install application packages from unknown sources, unless the app that requests the installation meets all the following requirements:

    • It MUST declare the REQUEST_INSTALL_PACKAGES permission or have the android:targetSdkVersion set at 24 or lower.
    • It MUST have been granted permission by the user to install apps from unknown sources.
  • SHOULD provide a user affordance to grant/revoke the permission to install apps from unknown sources per application, but MAY choose to implement this as a no-op and return RESULT_CANCELED for startActivityForResult() , if the device implementation does not want to allow users to have this choice. However, even in such cases, they SHOULD indicate to the user why there is no such choice presented.

5. 多媒體相容性

設備實現:

  • [C-0-1] MUST support the media formats, encoders, decoders, file types, and container formats defined in section 5.1 for each and every codec declared by MediaCodecList .
  • [C-0-2] MUST declare and report support of the encoders, decoders available to third-party applications via MediaCodecList .
  • [C-0-3] MUST be able to decode and make available to third-party apps all the formats it can encode. This includes all bitstreams that its encoders generate and the profiles reported in its CamcorderProfile .

設備實現:

  • SHOULD aim for minimum codec latency, in others words, they
    • SHOULD NOT consume and store input buffers and return input buffers only once processed.
    • SHOULD NOT hold onto decoded buffers for longer than as specified by the standard (eg SPS).
    • SHOULD NOT hold onto encoded buffers longer than required by the GOP structure.

All of the codecs listed in the section below are provided as software implementations in the preferred Android implementation from the Android Open Source Project.

請注意,Google和開放手機聯盟都沒有做出任何代碼器,即這些編解碼器沒有第三方專利。打算在硬體或軟體產品中使用此原始碼的人請注意,此程式碼的實現(包括在開源軟體或共享軟體中)可能需要相關專利持有者的專利許可。

5.1.媒體編解碼器

5.1.1.音訊編碼

See more details in 5.1.3. Audio Codecs Details .

If device implementations declare android.hardware.microphone , they MUST support the following audio encoding:

  • [C-1-1] PCM/WAVE

5.1.2.音訊解碼

See more details in 5.1.3. Audio Codecs Details .

If device implementations declare support for the android.hardware.audio.output feature, they must support the following audio decoders:

  • [C-1-1] MPEG-4 AAC Profile (AAC LC)
  • [C-1-2] MPEG-4 HE AAC Profile (AAC+)
  • [C-1-3] MPEG-4 HE AACv2 Profile (enhanced AAC+)
  • [C-1-4] AAC ELD (enhanced low delay AAC)
  • [C-1-5] FLAC
  • [C-1-6] MP3
  • [C-1-7] MIDI
  • [C-1-8] Vorbis
  • [C-1-9] PCM/WAVE
  • [C-1-10] Opus

If device implementations support the decoding of AAC input buffers of multichannel streams (ie more than two channels) to PCM through the default AAC audio decoder in the android.media.MediaCodec API, the following MUST be supported:

  • [C-2-1] Decoding MUST be performed without downmixing (eg a 5.0 AAC stream must be decoded to five channels of PCM, a 5.1 AAC stream must be decoded to six channels of PCM).
  • [C-2-2] Dynamic range metadata MUST be as defined in "Dynamic Range Control (DRC)" in ISO/IEC 14496-3, and the android.media.MediaFormat DRC keys to configure the dynamic range-related behaviors of the audio decoder. The AAC DRC keys were introduced in API 21,and are: KEY_AAC_DRC_ATTENUATION_FACTOR, KEY_AAC_DRC_BOOST_FACTOR, KEY_AAC_DRC_HEAVY_COMPRESSION, KEY_AAC_DRC_TARGET_REFERENCE_LEVEL and KEY_AAC_ENCODED_TARGET_LEVEL

5.1.3. Audio Codecs Details

Format/Codec細節Supported File Types/Container Formats
MPEG-4 AAC設定文件
(AAC LC)
Support for mono/stereo/5.0/5.1 content with standard sampling rates from 8 to 48 kHz.
  • 3GPP (.3gp)
  • MPEG-4(.mp4、.m4a)
  • ADTS raw AAC (.aac, ADIF not supported)
  • MPEG-TS (.ts, not seekable)
MPEG-4 HE AAC設定檔(AAC+) Support for mono/stereo/5.0/5.1 content with standard sampling rates from 16 to 48 kHz.
MPEG-4 HE AACV2
設定檔(增強AAC+)
Support for mono/stereo/5.0/5.1 content with standard sampling rates from 16 to 48 kHz.
AAC ELD(增強的低延遲AAC)支援單聲道/立體聲含量,標準取樣率從16到48 kHz。
AMR-NB 4.75 to 12.2 kbps sampled @ 8 kHz 3GPP (.3gp)
AMR-WB 9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16 kHz
FLAC單聲道/立體聲(無多聲道)。 Sample rates up to 48 kHz (but up to 44.1 kHz is RECOMMENDED on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler does not include a low-pass filter). 16-bit RECOMMENDED;沒有抖動適用於24位。僅FLAC(.flac)
MP3單一/立體聲8-320kbps常數(CBR)或可變位元率(VBR) MP3 (.mp3)
MIDI MIDI 類型 0 和 1。DLS 版本 1 和 2。XMF 和 Mobile XMF。支援鈴聲格式 RTTTL/RTX、OTA 和 iMelody
  • 類型0和1(.mid,.xmf,.mxmf)
  • rtttl/rtx(.rtttl,.rtx)
  • ota(.ota)
  • imelody(.imy)
沃爾比斯
  • 奧格 (.ogg)
  • Matroska (.mkv, Android 4.0+)
PCM/WAVE 16位元線性PCM(速率達到硬體限制)。設備必須支援8000、11025、16000和44100 Hz頻率的原始PCM記錄的取樣率。波形 (.wav)
作品Matroska (.mkv), Ogg(.ogg)

5.1.4.影像編碼

See more details in 5.1.6. Image Codecs Details .

Device implementations MUST support encoding the following image encoding:

  • [C-0-1] JPEG
  • [C-0-2] PNG
  • [C-0-3] WebP

5.1.5。 Image Decoding

See more details in 5.1.6. Image Codecs Details .

Device implementations MUST support encoding the following image decoding:

  • [C-0-1] JPEG
  • [C-0-2] GIF
  • [C-0-3] PNG
  • [C-0-4] BMP
  • [C-0-5] WebP
  • [C-0-6] Raw

5.1.6。 Image Codecs Details

Format/Codec細節Supported File Types/Container Formats
JPEG基礎+漸進式jpeg(.jpg)
動圖gif(.gif)
巴布亞紐幾內亞PNG (.png)
骨形態發生蛋白BMP(.bmp)
網路P WebP(.WEBP)
生的ARW (.arw), CR2 (.cr2), DNG (.dng), NEF (.nef), NRW (.nrw), ORF (.orf), PEF (.pef), RAF (.raf), RW2 (.rw2), SRW (.srw)

5.1.7.視訊編解碼器

  • For acceptable quality of web video streaming and video-conference services, device implementations SHOULD use a hardware VP8 codec that meets the requirements .

If device implementations include a video decoder or encoder:

  • [C-1-1] Video codecs MUST support output and input bytebuffer sizes that accommodate the largest feasible compressed and uncompressed frame as dictated by the standard and configuration but also not overallocate.

  • [C-1-2] Video encoders and decoders MUST support YUV420 flexible color format (COLOR_FormatYUV420Flexible).

If device implementations advertise HDR profile support through Display.HdrCapabilities , they:

  • [C-2-1] MUST support HDR static metadata parsing and handling.

If device implementations advertise intra refresh support through FEATURE_IntraRefresh in the MediaCodecInfo.CodecCapabilities class, they:

  • [C-3-1]MUST support the refresh periods in the range of 10 - 60 frames and accurately operate within 20% of configured refresh period.

5.1.8. Video Codecs List

Format/Codec細節Supported File Types/
容器格式
H.263
  • 3GPP (.3gp)
  • MPEG-4(.mp4)
H.264AVC有關詳細信息,請參見第5.2和5.3
  • 3GPP (.3gp)
  • MPEG-4(.mp4)
  • MPEG-2 TS (.ts, AAC audio only, not seekable, Android 3.0+)
H.265 HEVC有關詳細信息,請參見第5.3節MPEG-4(.mp4)
MPEG-2主要簡介MPEG2-TS
MPEG-4 sp 3GPP (.3gp)
VP8有關詳細信息,請參見第5.2和5.3
VP9有關詳細信息,請參見第5.3節

5.2.視訊編碼

If device implementations support any video encoder and make it available to third-party apps, they:

  • SHOULD NOT be, over two sliding windows, more than ~15% over the bitrate between intraframe (I-frame) intervals.
  • SHOULD NOT be more than ~100% over the bitrate over a sliding window of 1 second.

If device implementations include an embedded screen display with the diagonal length of at least 2.5 inches or include a video output port or declare the support of a camera via the android.hardware.camera.any feature flag, they:

  • [C-1-1] MUST include the support of at least one of the VP8 or H.264 video encoders, and make it available for third-party applications.
  • SHOULD support both VP8 and H.264 video encoders, and make it available for third-party applications.

If device implementations support any of the H.264, VP8, VP9 or HEVC video encoders and make it available to third-party applications, they:

  • [C-2-1] MUST support dynamically configurable bitrates.
  • SHOULD support variable frame rates, where video encoder SHOULD determine instantaneous frame duration based on the timestamps of input buffers, and allocate its bit bucket based on that frame duration.

If device implementations support the MPEG-4 SP video encoder and make it available to third-party apps, they:

  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.1. H.263

If device implementations support H.263 encoders and make it available to third-party apps, they:

  • [C-1-1] MUST support Baseline Profile Level 45.
  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.2. H-264

If device implementations support H.264 codec, they:

  • [C-1-1] MUST support Baseline Profile Level 3. However, support for ASO (Arbitrary Slice Ordering), FMO (Flexible Macroblock Ordering) and RS (Redundant Slices) is OPTIONAL. Moreover, to maintain compatibility with other Android devices, it is RECOMMENDED that ASO, FMO and RS are not used for Baseline Profile by encoders.
  • [C-1-2] MUST support the SD (Standard Definition) video encoding profiles in the following table.
  • SHOULD support Main Profile Level 4.
  • SHOULD support the HD (High Definition) video encoding profiles as indicated in the following table.

If device implementations report support of H.264 encoding for 720p or 1080p resolution videos through the media APIs, they:

  • [C-2-1] MUST support the encoding profiles in the following table.
SD(低品質) SD(高品質)高清720p高清1080p
視訊解析度320 x 240 PX 720 x 480 PX 1280 x 720 像素1920 x 1080 像素
視訊幀率20 幀/秒30 幀/秒30 幀/秒30 幀/秒
視訊比特率384 kbps 2Mbps 4Mbps 10Mbps

5.2.3. VP8

If device implementations support VP8 codec, they:

  • [C-1-1] MUST support the SD video encoding profiles.
  • SHOULD support the following HD (High Definition) video encoding profiles.
  • SHOULD support writing Matroska WebM files.
  • SHOULD use a hardware VP8 codec that meets the WebM project RTC hardware coding requirements , to ensure acceptable quality of web video streaming and video-conference services.

If device implementations report support of VP8 encoding for 720p or 1080p resolution videos through the media APIs, they:

  • [C-2-1] MUST support the encoding profiles in the following table.
SD(低品質) SD(高品質)高清720p高清1080p
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30 幀/秒
視訊比特率800 kbps 2Mbps 4Mbps 10Mbps

5.2.4. VP9

If device implementations support VP9 codec, they:

  • SHOULD support writing Matroska WebM files.

5.3.視訊解碼

If device implementations support VP8, VP9, H.264, or H.265 codecs, they:

  • [C-1-1] MUST support dynamic video resolution and frame rate switching through the standard Android APIs within the same stream for all VP8, VP9, H.264, and H.265 codecs in real time and up to the maximum resolution supported by each codec on the device.

If device implementations declare support for the Dolby Vision decoder through HDR_TYPE_DOLBY_VISION , they:

  • [C-2-1] MUST provide a Dolby Vision-capable extractor.
  • [C-2-2] MUST properly display Dolby Vision content on the device screen or on a standard video output port (eg, HDMI).
  • [C-2-3] MUST set the track index of backward-compatible base-layer(s) (if present) to be the same as the combined Dolby Vision layer's track index.

5.3.1. MPEG-2

If device implementations support MPEG-2 decoders, they:

  • [C-1-1] MUST support the Main Profile High Level.

5.3.2. H.263

If device implementations support H.263 decoders, they:

  • [C-1-1] MUST support Baseline Profile Level 30 and Level 45.

5.3.3. MPEG-4

If device implementations with MPEG-4 decoders, they:

  • [C-1-1] MUST support Simple Profile Level 3.

5.3.4. H.264

If device implementations support H.264 decoders, they:

  • [C-1-1] MUST support Main Profile Level 3.1 and Baseline Profile. Support for ASO (Arbitrary Slice Ordering), FMO (Flexible Macroblock Ordering) and RS (Redundant Slices) is OPTIONAL.
  • [C-1-2] MUST be capable of decoding videos with the SD (Standard Definition) profiles listed in the following table and encoded with the Baseline Profile and Main Profile Level 3.1 (including 720p30).
  • SHOULD be capable of decoding videos with the HD (High Definition) profiles as indicated in the following table.

If the height that is reported by the Display.getSupportedModes() method is equal or greater than the video resolution, device implementations:

  • [C-2-1] MUST support the HD 720p video decoding profiles in the following table.
  • [C-2-2] MUST support the HD 1080p video decoding profiles in the following table.
SD(低品質) SD(高品質)高清720p高清1080p
視訊解析度320 x 240 PX 720 x 480 PX 1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒60 幀/秒30 fps (60 fps Television )
視訊比特率800 kbps 2Mbps 8Mbps 20Mbps

5.3.5。 H.265 (HEVC)

If device implementations support H.265 codec, they:

  • [C-1-1] MUST support the Main Profile Level 3 Main tier and the SD video decoding profiles as indicated in the following table.
  • SHOULD support the HD decoding profiles as indicated in the following table.
  • [C-1-2] MUST support the HD decoding profiles as indicated in the following table if there is a hardware decoder.

If the height that is reported by the Display.getSupportedModes() method is equal to or greater than the video resolution, then:

  • [C-2-1] Device implementations MUST support at least one of H.265 or VP9 decoding of 720, 1080 and UHD profiles.
SD(低品質) SD(高品質)高清720p高清1080p超高畫質
視訊解析度352 x 288 PX 720 x 480 PX 1280 x 720 像素1920 x 1080 像素3840 x 2160 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30/60 fps (60 fps Television with H.265 hardware decoding ) 60 幀/秒
視訊比特率600 kbps 1.6 Mbps 4Mbps 5 Mbps 20Mbps

5.3.6。 VP8

If device implementations support VP8 codec, they:

  • [C-1-1] MUST support the SD decoding profiles in the following table.
  • SHOULD use a hardware VP8 codec that meets the requirements .
  • SHOULD support the HD decoding profiles in the following table.

If the height as reported by the Display.getSupportedModes() method is equal or greater than the video resolution, then:

  • [C-2-1] Device implementations MUST support 720p profiles in the following table.
  • [C-2-2] Device implementations MUST support 1080p profiles in the following table.
SD(低品質) SD(高品質)高清720p高清1080p
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒30 fps (60 fps Television ) 30 (60 fps Television )
視訊比特率800 kbps 2Mbps 8Mbps 20Mbps

5.3.7. VP9

If device implementations support VP9 codec, they:

  • [C-1-1] MUST support the SD video decoding profiles as indicated in the following table.
  • SHOULD support the HD decoding profiles as indicated in the following table.

If device implementations support VP9 codec and a hardware decoder:

  • [C-2-1] MUST support the HD decoding profiles as indicated in the following table.

If the height that is reported by the Display.getSupportedModes() method is equal to or greater than the video resolution, then:

  • [C-3-1] Device implementations MUST support at least one of VP9 or H.265 decoding of the 720, 1080 and UHD profiles.
SD(低品質) SD(高品質)高清720p高清1080p超高畫質
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素3840 x 2160 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30 fps (60 fps Television with VP9 hardware decoding ) 60 幀/秒
視訊比特率600 kbps 1.6 Mbps 4Mbps 5 Mbps 20Mbps

5.4.聲音錄製

While some of the requirements outlined in this section are listed as SHOULD since Android 4.3, the Compatibility Definition for future versions are planned to change these to MUST. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements that are listed as SHOULD, or they will not be able to attain Android compatibility when upgraded to the future version.

5.4.1.原始音訊捕獲

If device implementations declare android.hardware.microphone , they:

  • [C-1-1] MUST allow capture of raw audio content with the following characteristics:

    • 格式:線性PCM,16位
    • Sampling rates : 8000, 11025, 16000, 44100 Hz
    • 頻道:單聲道
  • [C-1-2] MUST capture at above sample rates without up-sampling.

  • [C-1-3] MUST include an appropriate anti-aliasing filter when the sample rates given above are captured with down-sampling.
  • SHOULD allow AM radio and DVD quality capture of raw audio content, which means the following characteristics:

    • 格式:線性PCM,16位
    • Sampling rates : 22050, 48000 Hz
    • 頻道:立體聲

If device implementations allow AM radio and DVD quality capture of raw audio content, they:

  • [C-2-1] MUST capture without up-sampling at any ratio higher than 16000:22050 or 44100:48000.
  • [C-2-2] MUST include an appropriate anti-aliasing filter for any up-sampling or down-sampling.

5.4.2.語音辨識捕獲

If device implementations declare android.hardware.microphone , they:

  • [C-1-1] MUST capture android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source at one of the sampling rates, 44100 and 48000.
  • [C-1-2] MUST, by default, disable any noise reduction audio processing when recording an audio stream from the AudioSource.VOICE_RECOGNITION audio source.
  • [C-1-3] MUST, by default, disable any automatic gain control when recording an audio stream from the AudioSource.VOICE_RECOGNITION audio source.
  • SHOULD record the voice recognition audio stream with approximately flat amplitude versus frequency characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
  • SHOULD record the voice recognition audio stream with input sensitivity set such that a 90 dB sound power level (SPL) source at 1000 Hz yields RMS of 2500 for 16-bit samples.
  • SHOULD record the voice recognition audio stream so that the PCM amplitude levels linearly track input SPL changes over at least a 30 dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
  • SHOULD record the voice recognition audio stream with total harmonic distortion (THD) less than 1% for 1 kHz at 90 dB SPL input level at the microphone.

If device implementations declare android.hardware.microphone and noise suppression (reduction) technologies tuned for speech recognition, they:

  • [C-2-1] MUST allow this audio affect to be controllable with the android.media.audiofx.NoiseSuppressor API.
  • [C-2-2] MUST uniquely identfiy each noise suppression technology implementation via the AudioEffect.Descriptor.uuid field.

5.4.3.捕獲以重新路由播放

android.media.MediaRecorder.AudioSource類別包含REMOTE_SUBMIX音訊來源。

If device implementations declare both android.hardware.audio.output and android.hardware.microphone , they:

  • [C-1-1] MUST properly implement the REMOTE_SUBMIX audio source so that when an application uses the android.media.AudioRecord API to record from this audio source, it captures a mix of all audio streams except for the following:

    • AudioManager.STREAM_RING
    • AudioManager.STREAM_ALARM
    • AudioManager.STREAM_NOTIFICATION

5.5.音訊播放

Android includes the support to allow apps to playback audio through the audio output peripheral as defined in section 7.8.2.

5.5.1.原始音訊播放

If device implementations declare android.hardware.audio.output , they:

  • [C-1-1] MUST allow playback of raw audio content with the following characteristics:

    • 格式:線性PCM,16位
    • 取樣率:8000,11025,16000,22050,32000,44100
    • 頻道:單,立體聲
  • SHOULD allow playback of raw audio content with the following characteristics:

    • 取樣率:24000,48000

5.5.2.音訊效果

Android provides an API for audio effects for device implementations.

If device implementations declare the feature android.hardware.audio.output , they:

  • [C-1-1] MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER implementations controllable through the AudioEffect subclasses Equalizer , LoudnessEnhancer .
  • [C-1-2] MUST support the visualizer API implementation, controllable through the Visualizer class.
  • SHOULD support the EFFECT_TYPE_BASS_BOOST , EFFECT_TYPE_ENV_REVERB , EFFECT_TYPE_PRESET_REVERB , and EFFECT_TYPE_VIRTUALIZER implementations controllable through the AudioEffect sub-classes BassBoost , EnvironmentalReverb , PresetReverb , and Virtualizer .

5.5.3.音訊輸出音量

Automotive device implementations:

  • SHOULD allow adjusting audio volume separately per each audio stream using the content type or usage as defined by AudioAttributes and car audio usage as publicly defined in android.car.CarAudioManager .

5.6.音訊延遲

音訊延遲是隨著音訊訊號通過系統的時間延遲。許多類別的應用程式都依賴短延遲來實現即時聲音效果。

出於本節的目的,請使用以下定義:

  • output latency . The interval between when an application writes a frame of PCM-coded data and when the corresponding sound is presented to environment at an on-device transducer or signal leaves the device via a port and can be observed externally.
  • cold output latency . The output latency for the first frame, when the audio output system has been idle and powered down prior to the request.
  • continuous output latency . The output latency for subsequent frames, after the device is playing audio.
  • input latency . The interval between when a sound is presented by environment to device at an on-device transducer or signal enters the device via a port and when an application reads the corresponding frame of PCM-coded data.
  • lost input . The initial portion of an input signal that is unusable or unavailable.
  • cold input latency . The sum of lost input time and the input latency for the first frame, when the audio input system has been idle and powered down prior to the request.
  • continuous input latency . The input latency for subsequent frames, while the device is capturing audio.
  • cold output jitter . The variability among separate measurements of cold output latency values.
  • cold input jitter . The variability among separate measurements of cold input latency values.
  • continuous round-trip latency . The sum of continuous input latency plus continuous output latency plus one buffer period. The buffer period allows time for the app to process the signal and time for the app to mitigate phase difference between input and output streams.
  • OpenSL ES PCM buffer queue API . The set of PCM-related OpenSL ES APIs within Android NDK .
  • AAudio native audio API . The set of AAudio APIs within Android NDK .

If device implementations declare android.hardware.audio.output they are STRONGLY RECOMMENDED to meet or exceed the following requirements:

  • [SR] Cold output latency of 100 milliseconds or less
  • [SR] Continuous output latency of 45 milliseconds or less
  • [SR] Minimize the cold output jitter

If device implementations meet the above requirements after any initial calibration when using the OpenSL ES PCM buffer queue API, for continuous output latency and cold output latency over at least one supported audio output device, they are:

  • [SR] STRONGLY RECOMMENDED to report low latency audio by declaring android.hardware.audio.low_latency feature flag.
  • [SR] STRONGLY RECOMMENDED to also meet the requirements for low-latency audio via the AAudio API.

If device implementations do not meet the requirements for low-latency audio via the OpenSL ES PCM buffer queue API, they:

  • [C-1-1] MUST NOT report support for low-latency audio.

If device implementations include android.hardware.microphone , they are STRONGLY RECOMMENDED to meet these input audio requirements:

  • [SR] Cold input latency of 100 milliseconds or less
  • [SR] Continuous input latency of 30 milliseconds or less
  • [SR] Continuous round-trip latency of 50 milliseconds or less
  • [SR] Minimize the cold input jitter

5.7.網路協定

Device implementations MUST support the media network protocols for audio and video playback as specified in the Android SDK documentation.

If device implementations include an audio or a video decoder, they:

  • [C-1-1] MUST support all required codecs and container formats in section 5.1 over HTTP(S).

  • [C-1-2] MUST support the media segment formats shown in the Media Segmant Formats table below over HTTP Live Streaming draft protocol, Version 7 .

  • [C-1-3] MUST support the following RTP audio video profile and related codecs in the RTSP table below. For exceptions please see the table footnotes in section 5.1 .

Media Segment Formats

Segment formats參考) Required codec support
MPEG-2 傳輸流ISO 13818 Video codecs:
  • H264 AVC
  • MPEG-4 sp
  • MPEG-2
See section 5.1.3 for details on H264 AVC, MPEG2-4 SP,
and MPEG-2.

Audio codecs:

  • 亞克力
See section 5.1.1 for details on AAC and its variants.
AAC with ADTS framing and ID3 tags ISO 13818-7 See section 5.1.1 for details on AAC and its variants
網路VTT網路VTT

RTSP(RTP,SDP)

個人資料名稱參考) Required codec support
H264 AVC RFC 6184 See section 5.1.3 for details on H264 AVC
MP4A-LATM RFC 6416 See section 5.1.1 for details on AAC and its variants
H263-1998 RFC 3551
RFC 4629
RFC 2190
See section 5.1.3 for details on H263
H263-2000 RFC 4629 See section 5.1.3 for details on H263
抗微生物藥物抗藥性RFC 4867 See section 5.1.1 for details on AMR-NB
AMR-WB RFC 4867 See section 5.1.1 for details on AMR-WB
MP4V-ES RFC 6416 See section 5.1.3 for details on MPEG-4 SP
mpeg4-generic RFC 3640 See section 5.1.1 for details on AAC and its variants
MP2T RFC 2250 See MPEG-2 Transport Stream underneath HTTP Live Streaming for details

5.8.安全媒體

If device implementations support secure video output and are capable of supporting secure surfaces, they:

  • [C-1-1] MUST declare support for Display.FLAG_SECURE .

If device implementations declare support for Display.FLAG_SECURE and support wireless display protocol, they:

  • [C-2-1] MUST secure the link with a cryptographically strong mechanism such as HDCP 2.x or higher for the displays connected through wireless protocols such as Miracast.

If device implementations declare support for Display.FLAG_SECURE and support wired external display, they:

  • [C-3-1] MUST support HDCP 1.2 or higher for all wired external displays.

5.9.樂器數位介面 (MIDI)

If a device implementation supports the inter-app MIDI software transport (virtual MIDI devices), and it supports MIDI over all of the following MIDI-capable hardware transports for which it provides generic non-MIDI connectivity, it is:

The MIDI-capable hardware transports are:

  • USB host mode (section 7.7 USB)
  • USB peripheral mode (section 7.7 USB)
  • MIDI over Bluetooth LE acting in central role (section 7.4.3 Bluetooth)

If the device implementation provides generic non-MIDI connectivity over a particular MIDI-capable hardware transport listed above, but does not support MIDI over that hardware transport, it:

  • [C-1-1] MUST NOT report support for feature android.software.midi.

5.10.專業音響

If device implementations report support for feature android.hardware.audio.pro via the android.content.pm.PackageManager class, they:

  • [C-1-1] MUST report support for feature android.hardware.audio.low_latency .
  • [C-1-2] MUST have the continuous round-trip audio latency, as defined in section 5.6 Audio Latency , MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one supported path.
  • [C-1-3] MUST include a USB port(s) supporting USB host mode and USB peripheral mode.
  • [C-1-4] MUST report support for feature android.software.midi .
  • [C-1-5] MUST meet latencies and USB audio requirements using the OpenSL ES PCM buffer queue API.
  • SHOULD provide a sustainable level of CPU performance while audio is active.
  • SHOULD minimize audio clock inaccuracy and drift relative to standard time.
  • SHOULD minimize audio clock drift relative to the CPU CLOCK_MONOTONIC when both are active.
  • SHOULD minimize audio latency over on-device transducers.
  • SHOULD minimize audio latency over USB digital audio.
  • SHOULD document audio latency measurements over all paths.
  • SHOULD minimize jitter in audio buffer completion callback entry times, as this affects usable percentage of full CPU bandwidth by the callback.
  • SHOULD provide zero audio underruns (output) or overruns (input) under normal use at reported latency.
  • SHOULD provide zero inter-channel latency difference.
  • SHOULD minimize MIDI mean latency over all transports.
  • SHOULD minimize MIDI latency variability under load (jitter) over all transports.
  • SHOULD provide accurate MIDI timestamps over all transports.
  • SHOULD minimize audio signal noise over on-device transducers, including the period immediately after cold start.
  • SHOULD provide zero audio clock difference between the input and output sides of corresponding end-points, when both are active. Examples of corresponding end-points include the on-device microphone and speaker, or the audio jack input and output.
  • SHOULD handle audio buffer completion callbacks for the input and output sides of corresponding end-points on the same thread when both are active, and enter the output callback immediately after the return from the input callback. Or if it is not feasible to handle the callbacks on the same thread, then enter the output callback shortly after entering the input callback to permit the application to have a consistent timing of the input and output sides.
  • SHOULD minimize the phase difference between HAL audio buffering for the input and output sides of corresponding end-points.
  • SHOULD minimize touch latency.
  • SHOULD minimize touch latency variability under load (jitter).

If device implementations meet all of the above requirements, they:

If device implementations meet the requirements via the OpenSL ES PCM buffer queue API, they:

  • [SR] STRONGLY RECOMMENDED to also meet the same requirements via the AAudio API.

If device implementations include a 4 conductor 3.5mm audio jack, they:

If device implementations omit a 4 conductor 3.5mm audio jack, they:

  • [C-3-1] MUST have a continuous round-trip audio latency of 20 milliseconds or less.
  • The continuous round-trip audio latency SHOULD be 10 milliseconds or less over the USB host mode port using USB audio class.

If device implementations include a USB port(s) supporting USB host mode, they:

  • [C-4-1] MUST implement the USB audio class.

If device implementations include an HDMI port, they:

  • [C-5-1] MUST support output in stereo and eight channels at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.

5.11.捕獲未處理的

Android includes support for recording of unprocessed audio via the android.media.MediaRecorder.AudioSource.UNPROCESSED audio source. In OpenSL ES, it can be accessed with the record preset SL_ANDROID_RECORDING_PRESET_UNPROCESSED .

If device implementations intent to support unprocessed audio source and make it available to third-party apps, they:

  • [C-1-1] MUST report the support through the android.media.AudioManager property PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED .

  • [C-1-2] MUST exhibit approximately flat amplitude-versus-frequency characteristics in the mid-frequency range: specifically ±10dB from 100 Hz to 7000 Hz for each and every microphone used to record the unprocessed audio source.

  • [C-1-3] MUST exhibit amplitude levels in the low frequency range: specifically from ±20 dB from 5 Hz to 100 Hz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.

  • [C-1-4] MUST exhibit amplitude levels in the high frequency range: specifically from ±30 dB from 7000 Hz to 22 KHz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.

  • [C-1-5] MUST set audio input sensitivity such that a 1000 Hz sinusoidal tone source played at 94 dB Sound Pressure Level (SPL) yields a response with RMS of 520 for 16 bit-samples (or -36 dB Full Scale for floating point/double precision samples) for each and every microphone used to record the unprocessed audio source.

  • [C-1-6] MUST have a signal-to-noise ratio (SNR) at 60 dB or higher for each and every microphone used to record the unprocessed audio source. (whereas the SNR is measured as the difference between 94 dB SPL and equivalent SPL of self noise, A-weighted).

  • [C-1-7] MUST have a total harmonic distortion (THD) less than be less than 1% for 1 kHZ at 90 dB SPL input level at each and every microphone used to record the unprocessed audio source.

  • MUST not have any other signal processing (eg Automatic Gain Control, High Pass Filter, or Echo cancellation) in the path other than a level multiplier to bring the level to desired range.換句話說:

  • [C-1-8] If any signal processing is present in the architecture for any reason, it MUST be disabled and effectively introduce zero delay or extra latency to the signal path.
  • [C-1-9] The level multiplier, while allowed to be on the path, MUST NOT introduce delay or latency to the signal path.

All SPL measurements are made directly next to the microphone under test. For multiple microphone configurations, these requirements apply to each microphone.

If device implementations declare android.hardware.microphone but do not support unprocessed audio source, they:

  • [C-2-1] MUST return null for the AudioManager.getProperty(PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED) API method, to properly indicate the lack of support.
  • [SR] are still STRONGLY RECOMMENDED to satisfy as many of the requirements for the signal path for the unprocessed recording source.

6. 開發者工具和選項相容性

6.1.開發者工具

設備實現:

  • [C-0-1] MUST support the Android Developer Tools provided in the Android SDK.
  • Android Debug Bridge (adb)

    • [C-0-2] MUST support all adb functions as documented in the Android SDK including dumpsys .
    • [C-0-3] MUST NOT alter the format or the contents of device system events (batterystats , diskstats, fingerprint, graphicsstats, netstats, notification, procstats) logged via dumpsys.
    • [C-0-4] MUST have the device-side adb daemon be inactive by default and there MUST be a user-accessible mechanism to turn on the Android Debug Bridge.
    • [C-0-5] MUST support secure adb. Android包含安全ADB的支援。安全ADB可以在已知身份驗證的宿主上啟用ADB。
    • [C-0-6] MUST provide a mechanism allowing adb to be connected from a host machine.例如:

      • Device implementations without a USB port supporting peripheral mode MUST implement adb via local-area network (such as Ethernet or Wi-Fi).
      • MUST provide drivers for Windows 7, 9 and 10, allowing developers to connect to the device using the adb protocol.
  • Dalvik Debug Monitor Service (ddms)

    • [C-0-7] MUST support all ddms features as documented in the Android SDK.由於DDMS使用ADB,因此預設情況下,對DDMS的支援應無效,但每當使用者啟動Android Debug Bridge(如上所述)時,必須支援DDMS。
    • [C-0-8] MUST include the Monkey framework and make it available for applications to use.
  • 系統追蹤
    • [C-0-9] MUST support systrace tool as documented in the Android SDK. Systrace must be inactive by default and there MUST be a user-accessible mechanism to turn on Systrace.

6.2.開發者選項

Android 支援開發人員配置應用程式開發相關的設定。

設備實現必須為開發者選項提供一致的體驗,它們:

  • [C-0-1] MUST honor the android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application development-related settings.預設情況下,上游Android實作會將「開發者選項」選單隱藏起來,並使使用者在設定> 「關於裝置」 > 「建置號碼」選單項目上按7(7)次之後啟動開發人員選項。
  • [C-0-2] MUST hide Developer Options by default and MUST provide a mechanism to enable Developer Options without the need for any special allowlisting.
  • MAY temporarily limit access to the Developer Options menu, by visually hiding or disabling the menu, to prevent distraction for scenarios where the safety of the user is of concern.

7. 硬體相容性

如果設備包含特定硬體元件,且該元件具有供第三方開發人員使用的對應 API:

  • [C-0-1] The device implementation MUST implement that API as described in the Android SDK documentation.

如果 SDK 中的 API 與指定為可選的硬體元件交互,且裝置實作不擁有該元件:

  • [C-0-2] Complete class definitions (as documented by the SDK) for the component APIs MUST still be presented.
  • [C-0-3] The API's behaviors MUST be implemented as no-ops in some reasonable fashion.
  • [C-0-4] API 方法必須在 SDK 文件允許的情況下傳回 null 值。
  • [C-0-5] API 方法必須傳回 SDK 文件不允許使用 null 值的類別的無操作實作。
  • [C-0-6] API 方法不得引發 SDK 文件未記錄的異常。
  • [C-0-7] Device implementations MUST consistently report accurate hardware configuration information via the getSystemAvailableFeatures() and hasSystemFeature(String) methods on the android.content.pm.PackageManager class for the same build fingerprint.

應用這些要求的場景的典型範例是電話 API:即使在非電話設備上,這些 API 也必須以合理的無操作方式實作。

7.1.顯示和圖形

Android 包含自動調整應用程式資源和適合裝置的 UI 佈局的功能,以確保第三方應用程式在各種硬體配置上運作良好。如本節所述,設備必須正確實施這些API和行為。

本節中要求所引用的單位定義如下:

  • physical diagonal size . The distance in inches between two opposing corners of the illuminated portion of the display.
  • dots per inch (dpi) . The number of pixels encompassed by a linear horizontal or vertical span of 1”. Where dpi values are listed, both horizontal and vertical dpi must fall within the range.
  • aspect ratio . The ratio of the pixels of the longer dimension to the shorter dimension of the screen. For example, a display of 480x854 pixels would be 854/480 = 1.779, or roughly “16:9”.
  • 與密度無關的像素 (dp) 。歸一化為 160 dpi 螢幕的虛擬像素單位,計算公式為:像素 = dps * (密度/160)。

7.1.1.螢幕配置

7.1.1.1.螢幕尺寸

The Android UI framework supports a variety of different logical screen layout sizes, and allows applications to query the current configuration's screen layout size via Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK and Configuration.smallestScreenWidthDp .

  • [C-0-1] Device implementations MUST report the correct layout size for the Configuration.screenLayout as defined in the Android SDK documentation.具體來說,設備實現必須報告正確的邏輯密度無關像素 (dp) 螢幕尺寸,如下所示:

    • Devices with the Configuration.uiMode set as any value other than UI_MODE_TYPE_WATCH, and reporting a small size for the Configuration.screenLayout , MUST have at least 426 dp x 320 dp.
    • Devices reporting a normal size for the Configuration.screenLayout , MUST have at least 480 dp x 320 dp.
    • Devices reporting a large size for the Configuration.screenLayout , MUST have at least 640 dp x 480 dp.
    • Devices reporting a xlarge size for the Configuration.screenLayout , MUST have at least 960 dp x 720 dp.
  • [C-0-2] Device implementations MUST correctly honor applications' stated support for screen sizes through the < supports-screens > attribute in the AndroidManifest.xml, as described in the Android SDK documentation.

7.1.1.2.螢幕縱橫比

While there is no restriction to the screen aspect ratio value of the physical screen display, the screen aspect ratio of the logical display that third-party apps are rendered within, as can be derived from the height and width values reported through the view.Display APIs and Configuration API, MUST meet the following requirements:

  • [C-0-1] Device implementations with the Configuration.uiMode set as UI_MODE_TYPE_NORMAL MUST have an aspect ratio value between 1.3333 (4:3) and 1.86 (roughly 16:9), unless the app can be deemed as ready to be stretched longer by meeting one of the following conditions:

    • The app has declared that it supports a larger screen aspect ratio through the android.max_aspect metadata value.
    • The app declares it is resizeable via the android:resizeableActivity attribute.
    • The app is targeting API level 24 or higher and does not declare a android:MaxAspectRatio that would restrict the allowed aspect ratio.
  • [C-0-2] Device implementations with the Configuration.uiMode set as UI_MODE_TYPE_WATCH MUST have an aspect ratio value set as 1.0 (1:1).

7.1.1.3。螢幕密度

Android UI 框架定義了一組標準邏輯密度來幫助應用程式開發人員定位應用程式資源。

  • [C-0-1] By default, device implementations MUST report only one of the following logical Android framework densities through the DENSITY_DEVICE_STABLE API and this value MUST NOT change at any time; however, the device MAY report a different arbitrary density according to the display configuration changes made by the user (for example, display size) set after initial boot.

    • 120 dpi(LDPI)
    • 160 dpi (mdpi)
    • 213 dpi(電視dpi)
    • 240 dpi(高清)
    • 260 dpi (260dpi)
    • 280dpi (280dpi)
    • 300 dpi (300dpi)
    • 320 dpi(xhdpi)
    • 340 dpi (340dpi)
    • 360dpi (360dpi)
    • 400dpi (400dpi)
    • 420 dpi (420dpi)
    • 480 dpi (xxhdpi)
    • 560dpi(560dpi)
    • 640 dpi (xxxhdpi)
  • 裝置實現應該定義在數值上最接近螢幕物理密度的標準 Android 框架密度,除非該邏輯密度將報告的螢幕尺寸推至支援的最小值以下。如果在數字上最接近物理密度的標準 Android 框架密度導致螢幕尺寸小於支援的最小相容螢幕尺寸(320 dp 寬度),則裝置實現應該報告下一個最低的標準 Android 框架密度。

如果可以變更設備的顯示尺寸:

  • [C-1-1] 顯示尺寸縮放後不得超過原始密度的 1.5 倍,也不得產生小於 320dp(相當於資源限定符 sw320dp)的有效最小螢幕尺寸(以先到者為準)。
  • [C-1-2] 顯示尺寸縮放後不得小於原始密度的 0.85 倍。
  • To ensure good usability and consistent font sizes, it is RECOMMENDED that the following scaling of Native Display options be provided (while complying with the limits specified above)
  • 小:0.85x
  • Default: 1x (Native display scale)
  • 大:1.15x
  • 更大:1.3x
  • Largest 1.45x

7.1.2.顯示指標

如果設備實作包括螢幕或視訊輸出,則它們:

如果裝置實作不包括嵌入式螢幕或視訊輸出,則:

  • [C-2-1] MUST report reasonable values for all display metrics defined in the android.util.DisplayMetrics API for the emulated default view.Display .

7.1.3.螢幕方向

設備實現:

  • [C-0-1] MUST report which screen orientations they support ( android.hardware.screen.portrait and/or android.hardware.screen.landscape ) and MUST report at least one supported orientation. For example, a device with a fixed orientation landscape screen, such as a television or laptop, SHOULD only report android.hardware.screen.landscape .
  • [C-0-2] MUST report the correct value for the device's current orientation, whenever queried via the android.content.res.Configuration.orientation , android.view.Display.getOrientation() , or other APIs.

如果設備實現支援兩種螢幕方向,則:

  • [C-1-1] 必須支援應用程式動態定向為縱向或橫向螢幕方向。也就是說,設備必須尊重應用程式對特定螢幕方向的請求。
  • [C-1-2] 更改方向時不得更改報告的螢幕尺寸或密度。
  • MAY select either portrait or landscape orientation as the default.

7.1.4. 2D 和 3D 圖形加速

7.1.4.1 OpenGL ES

設備實現:

  • [C-0-1] MUST correctly identify the supported OpenGL ES versions (1.1, 2.0, 3.0, 3.1, 3.2) through the managed APIs (such as via the GLES10.getString() method) and the native APIs.
  • [C-0-2] MUST include the support for all the corresponding managed APIs and native APIs for every OpenGL ES versions they identified to support.

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] MUST support both OpenGL ES 1.0 and 2.0, as embodied and detailed in the Android SDK documentation .
  • [SR] are STRONGLY RECOMMENDED to support OpenGL ES 3.0.
  • SHOULD support OpenGL ES 3.1 or 3.2.

If device implementations support any of the OpenGL ES versions, they:

  • [C-2-1] 必須透過 OpenGL ES 託管 API 和本機 API 報告它們已實現的任何其他 OpenGL ES 擴展,反之不得報告它們不支援的擴展字串。
  • [C-2-2] MUST support the EGL_KHR_image , EGL_KHR_image_base , EGL_ANDROID_image_native_buffer , EGL_ANDROID_get_native_client_buffer , EGL_KHR_wait_sync , EGL_KHR_get_all_proc_addresses , EGL_ANDROID_presentation_time , EGL_KHR_swap_buffers_with_damage and EGL_ANDROID_recordable extensions.
  • [SR] are STRONGLY RECOMMENDED to support EGL_KHR_partial_update.
  • SHOULD accurately report via the getString() method, any texture compression format that they support, which is typically vendor-specific.

如果裝置實作聲明支援 OpenGL ES 3.0、3.1 或 3.2,則:

  • [C-3-1] MUST export the corresponding function symbols for these version in addition to the OpenGL ES 2.0 function symbols in the libGLESv2.so library.

如果裝置實作支援 OpenGL ES 3.2,則:

  • [C-4-1] MUST support the OpenGL ES Android Extension Pack in its entirety.

如果裝置實作完全支援 OpenGL ES Android 擴充包,則:

  • [C-5-1] MUST identify the support through the android.hardware.opengles.aep feature flag.

If device implementations expose support for the EGL_KHR_mutable_render_buffer extension, they:

  • [C-6-1] MUST also support the EGL_ANDROID_front_buffer_auto_refresh extension.
7.1.4.2 伏爾甘

Android 支援Vulkan ,這是一種用於高效能 3D 圖形的低開銷、跨平台 API。

If device implementations support OpenGL ES 3.0 or 3.1, they:

  • [SR] Are STRONGLY RECOMMENDED to include support for Vulkan 1.0 .

如果設備實作包括螢幕或視訊輸出,則它們:

  • SHOULD include support for Vulkan 1.0.

Device implementations, if including support for Vulkan 1.0:

  • [C-1-1] MUST report the correct integer value with the android.hardware.vulkan.level and android.hardware.vulkan.version feature flags.
  • [C-1-2] MUST enumerate, at least one VkPhysicalDevice for the Vulkan native API vkEnumeratePhysicalDevices() .
  • [C-1-3] MUST fully implement the Vulkan 1.0 APIs for each enumerated VkPhysicalDevice .
  • [C-1-4] MUST enumerate layers, contained in native libraries named as libVkLayer*.so in the application package's native library directory, through the Vulkan native APIs vkEnumerateInstanceLayerProperties() and vkEnumerateDeviceLayerProperties() .
  • [C-1-5] MUST NOT enumerate layers provided by libraries outside of the application package, or provide other ways of tracing or intercepting the Vulkan API, unless the application has the android:debuggable attribute set as true .
  • [C-1-6] 必須報告它們透過 Vulkan 本機 API 支援的所有擴充字串,反之不得報告它們不正確支援的擴充字串。

Device implementations, if not including support for Vulkan 1.0:

  • [C-2-1] MUST NOT declare any of the Vulkan feature flags (eg android.hardware.vulkan.level , android.hardware.vulkan.version ).
  • [C-2-2] MUST NOT enumerate any VkPhysicalDevice for the Vulkan native API vkEnumeratePhysicalDevices() .
7.1.4.3 RenderScript
7.1.4.4 2D Graphics Acceleration

Android 包含一種機制,供應用程式透過使用清單標記android:hardwareAccelerated或直接 API 呼叫來聲明它們希望在應用程式、活動、視窗或視圖層級啟用 2D 圖形的硬體加速。

設備實現:

  • [C-0-1] 必須預設啟用硬體加速,如果開發者提出請求,則必須透過設定 android:hardwareAccelerated="false" 或直接透過 Android View API 停用硬體加速來停用硬體加速。
  • [C-0-2] MUST exhibit behavior consistent with the Android SDK documentation on hardware acceleration .

Android 包含一個 TextureView 對象,可讓開發人員直接將硬體加速的 OpenGL ES 紋理集成為 UI 層次結構中的渲染目標。

設備實現:

  • [C-0-3] 必須支援 TextureView API,並且必須表現出與上游 Android 實作一致的行為。
7.1.4.5 Wide-gamut Displays

If device implementations claim support for wide-gamut displays through Configuration.isScreenWideColorGamut() , they:

  • [C-1-1] 必須具有經過顏色校準的顯示器。
  • [C-1-2] MUST have a display whose gamut covers the sRGB color gamut entirely in CIE 1931 xyY space.
  • [C-1-3] MUST have a display whose gamut has an area of at least 90% of NTSC 1953 in CIE 1931 xyY space.
  • [C-1-4] MUST support OpenGL ES 3.0, 3.1, or 3.2 and report it properly.
  • [C-1-5] MUST advertise support for the EGL_KHR_no_config_context , EGL_EXT_pixel_format_float , EGL_KHR_gl_colorspace , EGL_EXT_colorspace_scrgb_linear , and EGL_GL_colorspace_display_p3 extensions.
  • [SR] Are STRONGLY RECOMMENDED to support GL_EXT_sRGB .

相反,如果設備實作不支援廣色域顯示,則:

  • [C-2-1] 儘管螢幕色域未定義,但應覆蓋 CIE 1931 xyY 空間中 100% 或更多的 sRGB。

7.1.5。舊版應用程式相容模式

Android 指定了一種“相容模式”,在該模式下,框架以“正常”螢幕尺寸等效(320dp 寬度)模式運行,以便為未針對螢幕尺寸獨立之前的舊版Android 開發的遺留應用程式帶來好處。

7.1.6。螢幕技術

Android平台包含允許應用程式將豐富圖形呈現為顯示的API。除非本文檔特別允許,否則裝置必須支援 Android SDK 定義的所有這些 API。

設備實現:

  • [C-0-1] MUST support displays capable of rendering 16-bit color graphics.
  • 應支援能夠顯示 24 位元彩色圖形的顯示器。
  • [C-0-2] MUST support displays capable of rendering animations.
  • [C-0-3] MUST use the display technology that have a pixel aspect ratio (PAR) between 0.9 and 1.15.也就是說,像素縱橫比必須在正方形(1.0)附近,公差為10〜15%。

7.1.7.輔助顯示器

Android包括對輔助顯示的支持,以啟用媒體共享功能和開發人員API,以存取外部顯示。

If device implementations support an external display either via a wired, wireless, or an embedded additional display connection, they:

  • [C-1-1] MUST implement the DisplayManager system service and API as described in the Android SDK documentation.

7.2.輸入裝置

設備實現:

7.2.1.鍵盤

If device implementations include support for third-party Input Method Editor (IME) applications, they:

Device implementations: [C-0-1] MUST NOT include a hardware keyboard that does not match one of the formats specified in android.content.res.Configuration.keyboard (QWERTY or 12-key). SHOULD include additional soft keyboard implementations. * MAY include a hardware keyboard.

7.2.2.非觸控式導航

Android 支援方向鍵、軌跡球和滾輪作為非觸控導航機制。

設備實現:

如果設備實現缺乏非觸控導航,它們:

  • [C-1-1] 必須提供合理的替代使用者介面機制來選擇和編輯文本,且與輸入管理引擎相容。上游 Android 開源實作包括適合與缺乏非觸控導航輸入的裝置一起使用的選擇機制。

7.2.3.導航鍵

The Home , Recents , and Back functions typically provided via an interaction with a dedicated physical button or a distinct portion of the touch screen, are essential to the Android navigation paradigm and therefore:

  • [C-0-1] MUST provide the Home function.
  • 應提供「最近使用」和「返回」功能的按鈕。

If the Home, Recents, or Back functions are provided, they:

  • [C-1-1] 當其中任何一個可存取時,必須可以透過單一操作(例如點擊、雙擊或手勢)進行存取。
  • [C-1-2] MUST provide a clear indication of which single action would trigger each function. Having a visible icon imprinted on the button, showing a software icon on the navigation bar portion of the screen, or walking the user through a guided step-by-step demo flow during the out- thr- through a guided step-by-step demo flow during the out- thr- through a guided step-by-step demo flow during the out-”指示。

設備實現:

  • [SR] are STRONGLY RECOMMENDED to not provide the input mechanism for the Menu function as it is deprecated in favor of action bar since Android 4.0.

如果設備實作提供選單功能,則它們:

  • [C-2-1] 只要操作溢出選單彈出視窗不為空且操作列可見,就必須顯示操作溢位按鈕。
  • [C-2-2] 不得透過選擇操作列中的溢出按鈕來修改操作溢出彈出視窗的位置,但可以在透過選擇選單顯示操作溢出彈出視窗時在螢幕上修改的位置呈現操作溢出彈出視窗功能。

If device implementations do not provide the Menu function, for backwards compatibility, they: * [C-3-1] MUST make the Menu function available to applications when targetSdkVersion is less than 10, wareeiton, asoft phys by asoft 10, wareeiton, phy0, wares , 0, wares by asoft physware, asoft 10, wares by asoft physware, 10, wares by physion, wares , 10, wareeiton, asoft 0, wares , 0, wares by asoft physware, 10, wares by asoft physware, 10, wares by asoft physware, 10, wareeiton, phy0, wares , 0, wares 認為 a手勢。 This Menu function should be accessible unless hidden together with other navigation functions.

If device implementations provide the Assist function , they: [C-4-1] MUST make the Assist function accessible with a single action (eg tap, double-click or gesture) when other navigation keys are accessible. [SR] STRONGLY RECOMMENDED to use long press on HOME function as this designated interaction.

如果裝置實作使用螢幕的不同部分來顯示導航鍵,則它們:

  • [C-5-1] 導航鍵必須使用應用程式不可用的螢幕特定部分,且不得遮蔽或以其他方式乾擾應用程式可用的螢幕部分。
  • [C-5-2] MUST make available a portion of the display to applications that meets the requirements defined in section 7.1.1 .
  • [C-5-3] MUST honor the flags set by the app through the View.setSystemUiVisibility() API method, so that this distinct portion of the screen (aka the navigation bar) is properly hidden away as documented in the SDK.

7.2.4.觸控螢幕輸入

Android includes support for a variety of pointer input systems, such as touchscreens, touch pads, and fake touch input devices. Touchscreen-based device implementations are associated with a display such that the user has the impression of directly manipulating items on screen.由於使用者直接接觸螢幕,因此系統不需要任何其他負擔來指示被操縱的物件。

設備實現:

  • 應該有某種類型的指標輸入系統(類似滑鼠或觸控)。
  • 應支援完全獨立追蹤的指針。

If device implementations include a touchscreen (single-touch or better), they:

  • [C-1-1] MUST report TOUCHSCREEN_FINGER for the Configuration.touchscreen API field.
  • [C-1-2] MUST report the android.hardware.touchscreen and android.hardware.faketouch feature flags

If device implementations include a touchscreen that can track more than a single touch, they:

  • [C-2-1] MUST report the appropriate feature flags android.hardware.touchscreen.multitouch , android.hardware.touchscreen.multitouch.distinct , android.hardware.touchscreen.multitouch.jazzhand corresponding to the type of the specific touchscreen on the裝置.

If device implementations do not include a touchscreen (and rely on a pointer device only) and meet the fake touch requirements in section 7.2.5 , they:

  • [C-3-1] MUST NOT report any feature flag starting with android.hardware.touchscreen and MUST report only android.hardware.faketouch .

7.2.5.假觸摸輸入

假觸控介面提供了近似觸控螢幕功能子集的使用者輸入系統。例如,驅動螢幕上遊標的滑鼠或遙控器類似於觸摸,但需要使用者先指向或聚焦,然後按一下。許多輸入裝置(例​​如滑鼠、觸控板、基於陀螺儀的空中滑鼠、陀螺儀指標、操縱桿和多點觸控觸控板)都可以支援假觸控互動。 Android 包含功能常數 android.hardware.faketouch,它對應於高保真非觸控(基於指針)輸入設備,例如可以充分模擬基於觸控的輸入(包括基本手勢支援)的滑鼠或觸控板,以及表示該設備支持觸控螢幕功能的模擬子集。

如果設備實現不包括觸控屏,但包括他們想要提供的另一個指針輸入系統,他們:

  • SHOULD declare support for the android.hardware.faketouch feature flag.

If device implementations declare support for android.hardware.faketouch , they:

  • [C-1-1] MUST report the absolute X and Y screen positions of the pointer location and display a visual pointer on the screen.
  • [C-1-2] 必須報告帶有操作代碼的觸控事件,該操作代碼指定指標在螢幕上向下或向上移動時發生的狀態變更。
  • [C-1-3] MUST support pointer down and up on an object on the screen, which allows users to emulate tap on an object on the screen.
  • [C-1-4] MUST support pointer down, pointer up, pointer down then pointer up in the same place on an object on the screen within a time threshold, which allows users to emulate double tap on an object on the screen.
  • [C-1-5] MUST support pointer down on an arbitrary point on the screen, pointer move to any other arbitrary point on the screen, followed by a pointer up, which allows users to emulate a touch drag.
  • [C-1-6] 必須支援指針向下,然後允許使用者快速將物件移動到螢幕上的不同位置,然後在螢幕上向上指針,以便使用者可以在螢幕上快速拖曳物件。
  • [C-1-7] MUST report TOUCHSCREEN_NOTOUCH for the Configuration.touchscreen API field.

If device implementations declare support for android.hardware.faketouch.multitouch.distinct , they:

  • [C-2-1] MUST declare support for android.hardware.faketouch .
  • [C-2-2] 必須支援對兩個或多個獨立指標輸入的不同追蹤。

If device implementations declare support for android.hardware.faketouch.multitouch.jazzhand , they:

  • [C-3-1] MUST declare support for android.hardware.faketouch .
  • [C-3-2] 必須完全獨立地支援 5 個(追蹤手指的手)或更多指針輸入的不同追蹤。

7.2.6。遊戲控制器支持

7.2.6.1.按鈕映射

If device implementations declare the android.hardware.gamepad feature flag , they: [C-1-1] MUST have embed a controller or ship with a separate controller in the box, that would provide means to input all the events list in the box, lowed invide means to input all events list表。 [C-1-2] MUST be capable to map HID events to it's associated Android view.InputEvent constants as listed in the below tables. The upstream Android implementation includes implementation for game controllers that satisfies this requirement.

按鈕HID 用法2安卓按鈕
1 0x09 0x0001 KEYCODE_BUTTON_A (96)
1 0x09 0x0002 KEYCODE_BUTTON_B (97)
X 1 0x09 0x0004 KEYCODE_BUTTON_X (99)
Y 1 0x09 0x0005 KEYCODE_BUTTON_Y (100)
D-pad up 1
D-pad down 1
0x01 0x0039 3 AXIS_HAT_Y 4
D-pad left 1
D-pad right 1
0x01 0x0039 3 AXIS_HAT_X 4
Left shoulder button 1 0x09 0x0007 KEYCODE_BUTTON_L1 (102)
右肩按鈕1 0x09 0x0008 KEYCODE_BUTTON_R1 (103)
左搖桿點選1 0x09 0x000E KEYCODE_BUTTON_THUMBL (106)
右搖桿點選1 0x09 0x000F KEYCODE_BUTTON_THUMBR (107)
首頁1 0x0c 0x0223 KEYCODE_HOME (3)
返回1 0x0c 0x0224 KEYCODE_BACK (4)

1關鍵事件

2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).

3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a Report Size of 4. The logical value is defined to be the clockwise rotation away from the vertical axis; for example, a logical value of 0 represents no rotation and the up button being pressed, while a logical value of 1 represents a rotation of 45 degrees and both the up and left keys being pressed.

4運動事件

模擬控制1 HID 使用安卓按鈕
左扳機0x02 0x00C5 AXIS_LTRIGGER
右邊扳機0x02 0x00C4 AXIS_RTRIGGER
左搖桿0x01 0x0030
0x01 0x0031
AXIS_X
AXIS_Y
右搖桿0x01 0x0032
0x01 0x0035
軸_Z
AXIS_RZ

1 個動作事件

7.2.7.遙控

有關設備特定要求,請參閱第 2.3.1 節

7.3.感應器

如果裝置實作包含特定的感測器類型,且該感測器類型具有供第三方開發人員使用的相應 API,則裝置實作必須實作該 API,如 Android SDK 文件和有關感測器的 Android 開源文件中所述。

設備實現:

  • [C-0-1] MUST accurately report the presence or absence of sensors per the android.content.pm.PackageManager class.
  • [C-0-2] MUST return an accurate list of supported sensors via the SensorManager.getSensorList() and similar methods.
  • [C-0-3] MUST behave reasonably for all other sensor APIs (for example, by returning true or false as appropriate when applications attempt to register listeners, not calling sensor listeners when the corresponding sensors are not present; etc.).

如果裝置實作包含特定感測器類型,且該感測器類型具有供第三方開發人員使用的對應 API,則它們:

  • [C-1-1] 必須使用 Android SDK 文件中定義的每種感測器類型的相關國際單位制(公制)值來報告所有感測器測量值
  • [C-1-2] MUST report sensor data with a maximum latency of 100 milliseconds
  • 2 * sample_time for the case of a sensor streamed with a minimum required latency of 5 ms + 2 * sample_time when the application processor is active.此延遲不包括任何過濾延遲。
  • [C-1-3] 必須在啟動感測器的 400 毫秒 + 2 * 樣本時間內報告第一個感測器樣本。此樣本的準確度為 0 是可以接受的。
  • [SR] SHOULD report the event time in nanoseconds as defined in the Android SDK documentation, representing the time the event happened and synchronized with the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases where this might become a REQUIRED component. The synchronization error SHOULD be below 100 milliseconds.

  • [C-1-4] For any API indicated by the Android SDK documentation to be a continuous sensor , device implementations MUST continuously provide periodic data samples that SHOULD have a jitter below 3%, where jitter is defined as the standard deviation of the difference of the reported timestamp values between consecutive events.

  • [C-1-5] 必須確保感測器事件流不得阻止裝置 CPU 進入暫停狀態或從暫停狀態喚醒。

  • 當多個感測器被啟動時,功耗不應超過各個感測器報告的功耗總和。

The list above is not comprehensive; the documented behavior of the Android SDK and the Android Open Source Documentations on sensors is to be considered authoritative.

某些感測器類型是複合的,這意味著它們可以從一個或多個其他感測器提供的數據中導出。 (例如方向感測器和線性加速度感測器。)

設備實現:

  • 當這些感測器類型包含感測器類型中所述的必備實體感測器時,應實現這些感測器類型。

如果設備實現包括複合感測器,則它們:

  • [C-2-1] MUST implement the sensor as described in the Android Open Source documentation on composite sensors .

7.3.1.加速度計

  • Device implementations SHOULD include a 3-axis accelerometer.

If device implementations include a 3-axis accelerometer, they:

  • [C-1-1] 必須能夠以至少 50 Hz 的頻率報告事件。
  • [C-1-2] MUST implement and report TYPE_ACCELEROMETER sensor.
  • [C-1-3] 必須符合 Android API 中詳述的Android 感測器座標系
  • [C-1-4] 必須能夠在任何軸上從自由落體到四倍重力 (4g) 或以上的情況下進行測量。
  • [C-1-5] 解析度必須至少為 12 位元。
  • [C-1-6] 標準差不得大於 0.05 m/s^,其中標準差應根據在至少 3 秒的時間內以最快採樣率收集的樣本按軸計算。
  • [SR] are STRONGLY RECOMMENDED to implement the TYPE_SIGNIFICANT_MOTION composite sensor.
  • [SR] are STRONGLY RECOMMENDED to implement the TYPE_ACCELEROMETER_UNCALIBRATED sensor if online accelerometer calibration is available.
  • SHOULD implement the TYPE_SIGNIFICANT_MOTION , TYPE_TILT_DETECTOR , TYPE_STEP_DETECTOR , TYPE_STEP_COUNTER composite sensors as described in the Android SDK document.
  • 應報告至少 200 Hz 的事件。
  • 分辨率應至少為 16 位元。
  • SHOULD be calibrated while in use if the characteristics changes over the life cycle and compensated, and preserve the compensation parameters between device reboots.
  • SHOULD be temperature compensated.
  • SHOULD also implement TYPE_ACCELEROMETER_UNCALIBRATED sensor.

If device implementations include a 3-axis accelerometer and any of the TYPE_SIGNIFICANT_MOTION , TYPE_TILT_DETECTOR , TYPE_STEP_DETECTOR , TYPE_STEP_COUNTER composite sensors are implemented:

  • [C-2-1] The sum of their power consumption MUST always be less than 4 mW.
  • SHOULD each be below 2 mW and 0.5 mW for when the device is in a dynamic or static condition.

If device implementations include a 3-axis accelerometer and a gyroscope sensor, they:

  • [C-3-1] MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors.
  • SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.

If device implementations include a 3-axis accelerometer, a gyroscope sensor and a magnetometer sensor, they:

  • [C-4-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

7.3.2.磁力計

  • Device implementations SHOULD include a 3-axis magnetometer (compass).

如果設備實現包括 3 軸磁力計,則:

  • [C-1-1] MUST implement the TYPE_MAGNETIC_FIELD sensor.
  • [C-1-2] 必須能夠以至少 10 Hz 的頻率報告事件,並且應該以至少 50 Hz 的頻率報告事件。
  • [C-1-3] 必須符合 Android API 中詳述的Android 感測器座標系
  • [C-1-4] MUST be capable of measuring between -900 µT and +900 µT on each axis before saturating.
  • [C-1-5] MUST have a hard iron offset value less than 700 µT and SHOULD have a value below 200 µT, by placing the magnetometer far from dynamic (current-induced) and static (magnet-induced) magnetic fields.
  • [C-1-6] 解析度必須等於或大於 0.6 µT。
  • [C-1-7] MUST support online calibration and compensation of the hard iron bias, and preserve the compensation parameters between device reboots.
  • [C-1-8] MUST have the soft iron compensation applied—the calibration can be done either while in use or during the production of the device.
  • [C-1-9] MUST have a standard deviation, calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate, no greater than 1.5 µT; SHOULD have a standard deviation no greater than 0.5 µT.
  • SHOULD implement TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.

If device implementations include a 3-axis magnetometer, an accelerometer sensor and a gyroscope sensor, they:

  • [C-2-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

If device implementations include a 3-axis magnetometer, an accelerometer, they:

  • MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor.

If device implementations include a 3-axis magnetometer, an accelerometer and TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor, they:

  • [C-3-1] 功耗必須低於 10 mW。
  • 當感測器註冊為 10 Hz 的批次模式時,功耗應低於 3 mW。

7.3.3.全球定位系統

設備實現:

  • SHOULD include a GPS/GNSS receiver.

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag, they:

  • [C-1-1] MUST support location outputs at a rate of at least 1 Hz when requested via LocationManager#requestLocationUpdate .
  • [C-1-2] MUST be able to determine the location in open-sky conditions (strong signals, negligible multipath, HDOP < 2) within 10 seconds (fast time to first fix), when connected to a 0.5 Mbps or faster data speed internet connection. This requirement is typically met by the use of some form of Assisted or Predicted GPS/GNSS technique to minimize GPS/GNSS lock-on time (Assistance data includes Reference Time, Reference Location and Satellite Ephemeris/Clock).
    • [SR] After making such a location calculation, it is STRONGLY RECOMMENDED for the device to be able to determine its location, in open sky, within 10 seconds, when location requests are restarted, up to an hour after the initial location calculation, even when the subsequent request is made without a data connection, and/or after a power cycle.
  • In open sky conditions after determining the location, while stationary or moving with less than 1 meter per second squared of acceleration:

    • [C-1-3] 必須能夠在至少 95% 的時間內確定 20 公尺範圍內的位置和每秒 0.5 公尺範圍內的速度。
    • [C-1-4] MUST simultaneously track and report via GnssStatus.Callback at least 8 satellites from one constellation.
    • 應能同時追蹤來自多個星座的至少 24 顆衛星(例如 GPS + 格洛納斯、北斗、伽利略中的至少一個)。
    • [C-1-5] MUST report the GNSS technology generation through the test API 'getGnssYearOfHardware'.
    • [SR] Continue to deliver normal GPS/GNSS location outputs during an emergency phone call.
    • [SR] Report GNSS measurements from all constellations tracked (as reported in GnssStatus messages), with the exception of SBAS.
    • [SR] Report AGC, and Frequency of GNSS measurement.
    • [SR] Report all accuracy estimates (including Bearing, Speed, and Vertical) as part of each GPS Location.
    • [SR] are STRONGLY RECOMMENDED to meet as many as possible from the additional mandatory requirements for devices reporting the year "2016" or "2017" through the Test API LocationManager.getGnssYearOfHardware() .

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag and the LocationManager.getGnssYearOfHardware() Test API reports the year "2016" or newer, they:

  • [C-2-1] MUST report GPS measurements, as soon as they are found, even if a location calculated from GPS/GNSS is not yet reported.
  • [C-2-2] MUST report GPS pseudoranges and pseudorange rates, that, in open-sky conditions after determining the location, while stationary or moving with less than 0.2 meter per second squared of acceleration, are sufficient to calculate position within 20 meters, and speed within 0.2 meters per second, at least 95% of the time.

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag and the LocationManager.getGnssYearOfHardware() Test API reports the year "2017" or newer, they:

  • [C-3-1] MUST continue to deliver normal GPS/GNSS location outputs during an emergency phone call.
  • [C-3-2] MUST report GNSS measurements from all constellations tracked (as reported in GnssStatus messages), with the exception of SBAS.
  • [C-3-3] MUST report AGC, and Frequency of GNSS measurement.
  • [C-3-4] MUST report all accuracy estimates (including Bearing, Speed, and Vertical) as part of each GPS Location.

7.3.4.陀螺儀

設備實現:

  • SHOULD include a gyroscope (angular change sensor).
  • SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is also included.

If device implementations include a gyroscope, they:

  • [C-1-1] 必須能夠以至少 50 Hz 的頻率報告事件。
  • [C-1-2] MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement TYPE_GYROSCOPE_UNCALIBRATED sensor.
  • [C-1-3] MUST be capable of measuring orientation changes up to 1,000 degrees per second.
  • [C-1-4] MUST have a resolution of 12-bits or more and SHOULD have a resolution of 16-bits or more.
  • [C-1-5] 必須進行溫度補償。
  • [C-1-6] MUST be calibrated and compensated while in use, and preserve the compensation parameters between device reboots.
  • [C-1-7] 每 Hz 的變異數不得大於 1e-7 rad^2 / s^2(每 Hz 的方差,或 rad^2 / s)。方差允許隨取樣率變化,但必須受此值的約束。換句話說,如果以 1 Hz 取樣率測量陀螺儀的方差,它應該不大於 1e-7 rad^2/s^2。
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.
  • [SR] Calibration error is STRONGLY RECOMMENDED to be less than 0.01 rad/s when device is stationary at room temperature.
  • 應報告至少 200 Hz 的事件。

If device implementations include a gyroscope, an accelerometer sensor and a magnetometer sensor, they:

  • [C-2-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

If device implementations include a gyroscope and a accelerometer sensor, they:

  • [C-3-1] MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.
  • SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor.

7.3.5。晴雨表

  • Device implementations SHOULD include a barometer (ambient air pressure sensor).

If device implementations include a barometer, they:

  • [C-1-1] MUST implement and report TYPE_PRESSURE sensor.
  • [C-1-2] 必須能夠以 5 Hz 或更高頻率傳送事件。
  • [C-1-3] MUST be temperature compensated.
  • [SR] STRONGLY RECOMMENDED to be able to report pressure measurements in the range 300hPa to 1100hPa.
  • SHOULD have an absolute accuracy of 1hPa.
  • SHOULD have a relative accuracy of 0.12hPa over 20hPa range (equivalent to ~1m accuracy over ~200m change at sea level).

7.3.6。溫度計

Device implementations: MAY include an ambient thermometer (temperature sensor). MAY but SHOULD NOT include a CPU temperature sensor.

如果設備實現包括環境溫度計(溫度感測器),則它們:

  • [C-1-1] MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and MUST measure the ambient (room/vehicle cabin) temperature from where the user is interacting with the device in degrees Celsius.
  • [C-1-2] MUST be defined as SENSOR_TYPE_TEMPERATURE .
  • [C-1-3] MUST measure the temperature of the device CPU.
  • [C-1-4] MUST NOT measure any other temperature.

Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.

7.3.7.光度計

  • 設備實現可以包括光度計(環境光感測器)。

7.3.8.接近感測器

  • 設備實現可以包括接近感測器。

If device implementations include a proximity sensor, they:

  • [C-1-1] 必須測量與螢幕相同方向的物體的接近度。也就是說,接近感測器的方向必須能夠偵測靠近螢幕的物體,因為這種感測器類型的主要目的是偵測使用者正在使用的手機。如果裝置實作包括任何其他方向的接近感測器,則不得透過此 API 存取它。
  • [C-1-2] MUST have 1-bit of accuracy or more.

7.3.9.高保真感應器

If device implementations include a set of higher quality sensors as defined in this section, and make available them to third-party apps, they:

  • [C-1-1] MUST identify the capability through the android.hardware.sensor.hifi_sensors feature flag.

If device implementations declare android.hardware.sensor.hifi_sensors , they:

  • [C-2-1] MUST have a TYPE_ACCELEROMETER sensor which:

    • MUST have a measurement range between at least -8g and +8g.
    • MUST have a measurement resolution of at least 1024 LSB/G.
    • 最小測量頻率必須為 12.5 Hz 或更低。
    • MUST have a maximum measurement frequency of 400 Hz or higher.
    • MUST have a measurement noise not above 400 uG/√Hz.
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 3000 sensor events.
    • 批次功耗必須不低於 3 mW。
    • SHOULD have a stationary noise bias stability of \<15 μg √Hz from 24hr static dataset.
    • SHOULD have a bias change vs. temperature of ≤ +/- 1mg / °C.
    • 最佳擬合線非線性度應≤ 0.5%,靈敏度隨溫度的變化應≤ 0.03%/C°。
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
  • [C-2-2] MUST have a TYPE_ACCELEROMETER_UNCALIBRATED with the same quality requirements as TYPE_ACCELEROMETER .

  • [C-2-3] MUST have a TYPE_GYROSCOPE sensor which:

    • MUST have a measurement range between at least -1000 and +1000 dps.
    • 測量解析度必須至少為 16 LSB/dps。
    • 最小測量頻率必須為 12.5 Hz 或更低。
    • MUST have a maximum measurement frequency of 400 Hz or higher.
    • MUST have a measurement noise not above 0.014°/s/√Hz.
    • SHOULD have a stationary bias stability of < 0.0002 °/s √Hz from 24-hour static dataset.
    • SHOULD have a bias change vs. temperature of ≤ +/- 0.05 °/ s / °C.
    • SHOULD have a sensitivity change vs. temperature of ≤ 0.02% / °C.
    • SHOULD have a best-fit line non-linearity of ≤ 0.2%.
    • 噪音密度應≤ 0.007 °/s/√Hz。
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
    • 當設備靜止時,在 10 ~ 40 ℃ 溫度範圍內,校準誤差應小於 0.002 rad/s。
  • [C-2-4] MUST have a TYPE_GYROSCOPE_UNCALIBRATED with the same quality requirements as TYPE_GYROSCOPE .

  • [C-2-5] MUST have a TYPE_GEOMAGNETIC_FIELD sensor which:
    • MUST have a measurement range between at least -900 and +900 uT.
    • 測量解析度必須至少為 5 LSB/uT。
    • 最小測量頻率必須為 5 Hz 或更低。
    • MUST have a maximum measurement frequency of 50 Hz or higher.
    • MUST have a measurement noise not above 0.5 uT.
  • [C-2-6] MUST have a TYPE_MAGNETIC_FIELD_UNCALIBRATED with the same quality requirements as TYPE_GEOMAGNETIC_FIELD and in addition:
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 600 sensor events.
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
  • [C-2-7] MUST have a TYPE_PRESSURE sensor which:
    • MUST have a measurement range between at least 300 and 1100 hPa.
    • 測量分辨率必須至少為 80 LSB/hPa。
    • 最小測量頻率必須為 1 Hz 或更低。
    • 最大測量頻率必須為 10 Hz 或更高。
    • 量測雜訊必須不高於 2 Pa/√Hz。
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events.
    • MUST have a batching power consumption not worse than 2 mW.
  • [C-2-8] MUST have a TYPE_GAME_ROTATION_VECTOR sensor which:
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events.
    • MUST have a batching power consumption not worse than 4 mW.
  • [C-2-9] MUST have a TYPE_SIGNIFICANT_MOTION sensor which:
    • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
  • [C-2-10] MUST have a TYPE_STEP_DETECTOR sensor which:
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 100 sensor events.
    • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
    • MUST have a batching power consumption not worse than 4 mW.
  • [C-2-11] MUST have a TYPE_STEP_COUNTER sensor which:
    • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
  • [C-2-12] MUST have a TILT_DETECTOR sensor which:
    • MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
  • [C-2-13] The event timestamp of the same physical event reported by the Accelerometer, Gyroscope sensor and Magnetometer MUST be within 2.5 milliseconds of each other.
  • [C-2-14] 陀螺儀感測器事件時間戳記必須與相機子系統處於同一時基,且誤差在 1 毫秒以內。
  • [C-2-15] 當上述任何實體感測器上的資料可用於應用程式時,必須在 5 毫秒內將樣本傳送到應用程式。
  • [C-2-16] MUST not have a power consumption higher than 0.5 mW when device is static and 2.0 mW when device is moving when any combination of the following sensors are enabled:
    • SENSOR_TYPE_SIGNIFICANT_MOTION
    • SENSOR_TYPE_STEP_DETECTOR
    • SENSOR_TYPE_STEP_COUNTER
    • SENSOR_TILT_DETECTORS
  • [C-2-17] MAY have a TYPE_PROXIMITY sensor, but if present MUST have a minimum buffer capability of 100 sensor events.

請注意,本節中的所有功耗要求不包括應用處理器的功耗。它包括整個感測器鏈(感測器、任何支援電路、任何專用感測器處理系統等)消耗的功率。

If device implementations include direct sensor support, they:

  • [C-3-1] MUST correctly declare support of direct channel types and direct report rates level through the isDirectChannelTypeSupported and getHighestDirectReportRateLevel API.
  • [C-3-2] MUST support at least one of the two sensor direct channel types for all sensors that declare support for sensor direct channel
  • TYPE_HARDWARE_BUFFER
  • TYPE_MEMORY_FILE
  • 應支援透過感測器直接通道對以下類型的主感測器(非喚醒變體)進行事件報告:
  • TYPE_ACCELEROMETER
  • TYPE_ACCELEROMETER_UNCALIBRATED
  • TYPE_GYROSCOPE
  • TYPE_GYROSCOPE_UNCALIBRATED
  • TYPE_MAGNETIC_FIELD
  • TYPE_MAGNETIC_FIELD_UNCALIBRATED

7.3.10.指紋感應器

If device implementations include a secure lock screen, they:

  • SHOULD include a fingerprint sensor.

If device implementations include a fingerprint sensor and make the sensor available to third-party apps, they:

  • [C-1-1] MUST declare support for the android.hardware.fingerprint feature.
  • [C-1-2] MUST fully implement the corresponding API as described in the Android SDK documentation.
  • [C-1-3] MUST have a false acceptance rate not higher than 0.002%.
  • [C-1-4] MUST rate limit attempts for at least 30 seconds after five false trials for fingerprint verification.
  • [C-1-5] MUST have a hardware-backed keystore implementation, and perform the fingerprint matching in a Trusted Execution Environment (TEE) or on a chip with a secure channel to the TEE.
  • [C-1-6] MUST have all identifiable fingerprint data encrypted and cryptographically authenticated such that they cannot be acquired, read or altered outside of the Trusted Execution Environment (TEE) as documented in the implementation guidelines on the Android Open Source Project site.
  • [C-1-7] MUST prevent adding a fingerprint without first establishing a chain of trust by having the user confirm existing or add a new device credential (PIN/pattern/password) that's secured by TEE; the Android Open Source Project implementation provides the mechanism in the framework to do so.
  • [C-1-8] MUST NOT enable 3rd-party applications to distinguish between individual fingerprints.
  • [C-1-9] MUST honor the DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT flag.
  • [C-1-10] MUST, when upgraded from a version earlier than Android 6.0, have the fingerprint data securely migrated to meet the above requirements or removed.
  • [SR] STRONGLY RECOMMENDED to have a false rejection rate of less than 10%, as measured on the device.
  • [SR] STRONGLY RECOMMENDED to have a latency below 1 second, measured from when the fingerprint sensor is touched until the screen is unlocked, for one enrolled finger.
  • SHOULD use the Android Fingerprint icon provided in the Android Open Source Project.

7.3.11. Android Automotive-only sensors

Automotive-specific sensors are defined in the android.car.CarSensorManager API .

7.3.11.1.目前檔位

See Section 2.5.1 for device-specific requirements.

7.3.11.2. Day Night Mode

See Section 2.5.1 for device-specific requirements.

7.3.11.3.駕駛狀態

See Section 2.5.1 for device-specific requirements.

7.3.11.4. Wheel Speed

See Section 2.5.1 for device-specific requirements.

7.3.12.姿勢感測器

設備實現:

  • MAY support pose sensor with 6 degrees of freedom.

If device implementations support pose sensor with 6 degrees of freedom, they:

  • [C-1-1] MUST implement and report TYPE_POSE_6DOF sensor.
  • [C-1-2] 必須比單獨的旋轉向量更準確。

7.4.數據連接

7.4.1.電話

Android API 和本文檔中使用的「電話」特別指與透過 GSM 或 CDMA 網路撥打語音電話和發送 SMS 訊息相關的硬體。雖然這些語音通話可能會也可能不會進行資料包交換,但出於 Android 的目的,它們被視為獨立於可能使用相同網路實現的任何資料連線。換句話說,Android「電話」功能和 API 特指語音通話和簡訊。例如,無法撥打電話或發送/接收 SMS 訊息的設備實作不被視為電話設備,無論它們是否使用蜂窩網路進行數據連接。

  • Android 可以在不包含電話硬體的裝置上使用。也就是說,Android 相容於手機以外的裝置。

如果設備實作包括 GSM 或 CDMA 電話,則:

  • [C-1-1] MUST declare the android.hardware.telephony feature flag and other sub-feature flags according to the technology.
  • [C-1-2] MUST implement full support for the API for that technology.

If device implementations do not include telephony hardware, they:

  • [C-2-1] 必須將完整 API 實作為無操作。
7.4.1.1. Number Blocking Compatibility

If device implementations report the android.hardware.telephony feature , they:

  • [C-1-1] MUST include number blocking support
  • [C-1-2] MUST fully implement BlockedNumberContract and the corresponding API as described in the SDK documentation.
  • [C-1-3] MUST block all calls and messages from a phone number in 'BlockedNumberProvider' without any interaction with apps. The only exception is when number blocking is temporarily lifted as described in the SDK documentation.
  • [C-1-4] MUST NOT write to the platform call log provider for a blocked call.
  • [C-1-5] MUST NOT write to the Telephony provider for a blocked message.
  • [C-1-6] MUST implement a blocked numbers management UI, which is opened with the intent returned by TelecomManager.createManageBlockedNumbersIntent() method.
  • [C-1-7] MUST NOT allow secondary users to view or edit the blocked numbers on the device as the Android platform assumes the primary user to have full control of the telephony services, a single instance, on the device. All blocking related UI MUST be hidden for secondary users and the blocked list MUST still be respected.
  • SHOULD migrate the blocked numbers into the provider when a device updates to Android 7.0.

7.4.2. IEEE 802.11(無線網路)

設備實現:

  • SHOULD include support for one or more forms of 802.11.

If device implementations include support for 802.11 and expose the functionality to a third-party application, they:

  • [C-1-1] MUST implement the corresponding Andr:oid API.
  • [C-1-2] MUST report the hardware feature flag android.hardware.wifi .
  • [C-1-3] MUST implement the multicast API as described in the SDK documentation.
  • [C-1-4] MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets (224.0.0.251) at any time of operation including:
    • Even when the screen is not in an active state.
    • For Android Television device implementations, even when in standby power states.
  • SHOULD randomize the source MAC address and sequence number of probe request frames, once at the beginning of each scan, while STA is disconnected.
    • Each group of probe request frames comprising one scan should use one consistent MAC address (SHOULD NOT randomize MAC address halfway through a scan).
    • Probe request sequence number should iterate as normal (sequentially) between the probe requests in a scan
    • Probe request sequence number should randomize between the last probe request of a scan and the first probe request of the next scan
  • SHOULD only allow the following information elements in probe request frames, while STA is disconnected:
    • SSID Parameter Set (0)
    • DS Parameter Set (3)
7.4.2.1.無線直連

設備實現:

  • SHOULD include support for Wi-Fi Direct (Wi-Fi peer-to-peer).

If device implementations include support for Wi-Fi Direct, they:

  • [C-1-1] MUST implement the corresponding Android API as described in the SDK documentation.
  • [C-1-2] MUST report the hardware feature android.hardware.wifi.direct .
  • [C-1-3] MUST support regular Wi-Fi operation.
  • SHOULD support Wi-Fi and Wi-Fi Direct operations concurrently.

設備實現:

If device implementations include support for TDLS and TDLS is enabled by the WiFiManager API, they:

  • [C-1-1] MUST declare support for TDLS through WifiManager.isTdlsSupported .
  • SHOULD use TDLS only when it is possible AND beneficial.
  • SHOULD have some heuristic and NOT use TDLS when its performance might be worse than going through the Wi-Fi access point.
7.4.2.3.無線網路感知

設備實現:

If device implementations include support for Wi-Fi Aware and expose the functionality to third-party apps, then they:

  • [C-1-1] MUST implement the WifiAwareManager APIs as described in the SDK documentation .
  • [C-1-2] MUST declare the android.hardware.wifi.aware feature flag.
  • [C-1-3] MUST support Wi-Fi and Wi-Fi Aware operations concurrently.
  • [C-1-4] MUST randomize the Wi-Fi Aware management interface address at intervals no longer then 30 minutes and whenever Wi-Fi Aware is enabled.
7.4.2.4. Wi-Fi 通行點

設備實現:

If device implementations include support for Wi-Fi Passpoint, they:

  • [C-1-1] MUST implement the Passpoint related WifiManager APIs as described in the SDK documentation .
  • [C-1-2] MUST support IEEE 802.11u standard, specifically related to Network Discovery and Selection, such as Generic Advertisement Service (GAS) and Access Network Query Protocol (ANQP).

Conversely if device implementations do not include support for Wi-Fi Passpoint:

  • [C-2-1] The implementation of the Passpoint related WifiManager APIs MUST throw an UnsupportedOperationException .

7.4.3.藍牙

If device implementations support Bluetooth Audio profile, they:

  • SHOULD support Advanced Audio Codecs and Bluetooth Audio Codecs (eg LDAC).

If device implementations declare android.hardware.vr.high_performance feature, they:

  • [C-1-1] MUST support Bluetooth 4.2 and Bluetooth LE Data Length Extension.

Android includes support for Bluetooth and Bluetooth Low Energy .

If device implementations include support for Bluetooth and Bluetooth Low Energy, they:

  • [C-2-1] MUST declare the relevant platform features ( android.hardware.bluetooth and android.hardware.bluetooth_le respectively) and implement the platform APIs.
  • SHOULD implement relevant Bluetooth profiles such as A2DP, AVCP, OBEX, etc. as appropriate for the device.

If device implementations include support for Bluetooth Low Energy, they:

  • [C-3-1] MUST declare the hardware feature android.hardware.bluetooth_le .
  • [C-3-2] MUST enable the GATT (generic attribute profile) based Bluetooth APIs as described in the SDK documentation and android.bluetooth .
  • [C-3-3] MUST report the correct value for BluetoothAdapter.isOffloadedFilteringSupported() to indicate whether the filtering logic for the ScanFilter API classes is implemented.
  • [C-3-4] MUST report the correct value for BluetoothAdapter.isMultipleAdvertisementSupported() to indicate whether Low Energy Advertising is supported.
  • SHOULD support offloading of the filtering logic to the bluetooth chipset when implementing the ScanFilter API .
  • SHOULD support offloading of the batched scanning to the bluetooth chipset.
  • SHOULD support multi advertisement with at least 4 slots.

  • [SR] STRONGLY RECOMMENDED to implement a Resolvable Private Address (RPA) timeout no longer than 15 minutes and rotate the address at timeout to protect user privacy.

7.4.4.近場通訊

設備實現:

  • SHOULD include a transceiver and related hardware for Near-Field Communications (NFC).
  • [C-0-1] MUST implement android.nfc.NdefMessage and android.nfc.NdefRecord APIs even if they do not include support for NFC or declare the android.hardware.nfc feature as the classes represent a declare the android.hardware.nfc feature as the classes represent a protocol-presmatent as the classs represent a protocol. 。

If device implementations include NFC hardware and plan to make it available to third-party apps, they:

  • [C-1-1] MUST report the android.hardware.nfc feature from the android.content.pm.PackageManager.hasSystemFeature() method .
  • MUST be capable of reading and writing NDEF messages via the following NFC standards as below:
  • [C-1-2] MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the following NFC standards:
    • NfcA (ISO14443-3A)
    • NfcB (ISO14443-3B)
    • NfcF (JIS X 6319-4)
    • IsoDep (ISO 14443-4)
    • NFC Forum Tag Types 1, 2, 3, 4, 5 (defined by the NFC Forum)
  • [SR] STRONGLY RECOMMENDED to be capable of reading and writing NDEF messages as well as raw data via the following NFC standards. Note that while the NFC standards are stated as STRONGLY RECOMMENDED, the Compatibility Definition for a future version is planned to change these to MUST. These standards are optional in this version but will be required in future versions. Existing and new devices that run this version of Android are very strongly encouraged to meet these requirements now so they will be able to upgrade to the future platform releases.

  • [C-1-3] MUST be capable of transmitting and receiving data via the following peer-to-peer standards and protocols:

    • ISO 18092
    • LLCP 1.2 (defined by the NFC Forum)
    • SDP 1.0 (defined by the NFC Forum)
    • NDEF Push Protocol
    • SNEP 1.0 (defined by the NFC Forum)
  • [C-1-4] MUST include support for Android Beam and SHOULD enable Android Beam by default.
  • [C-1-5] MUST be able to send and receive using Android Beam, when Android Beam is enabled or another proprietary NFC P2p mode is turned on.
  • [C-1-6] MUST implement the SNEP default server. Valid NDEF messages received by the default SNEP server MUST be dispatched to applications using the android.nfc.ACTION_NDEF_DISCOVERED intent. Disabling Android Beam in settings MUST NOT disable dispatch of incoming NDEF message.
  • [C-1-7] MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing settings .
  • [C-1-8] MUST implement the NPP server. Messages received by the NPP server MUST be processed the same way as the SNEP default server.
  • [C-1-9] MUST implement a SNEP client and attempt to send outbound P2P NDEF to the default SNEP server when Android Beam is enabled. If no default SNEP server is found then the client MUST attempt to send to an NPP server.
  • [C-1-10] MUST allow foreground activities to set the outbound P2P NDEF message using android.nfc.NfcAdapter.setNdefPushMessage , and android.nfc.NfcAdapter.setNdefPushMessageCallback , and android.nfc.NfcAdapter.enableForegroundNdefPush .
  • SHOULD use a gesture or on-screen confirmation, such as 'Touch to Beam', before sending outbound P2P NDEF messages.
  • [C-1-11] MUST support NFC Connection handover to Bluetooth when the device supports Bluetooth Object Push Profile.
  • [C-1-12] MUST support connection handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris , by implementing the “ Connection Handover version 1.2 ” and “ Bluetooth Secure Simple Pairing Using NFC version 1.0 ” specs from the NFC Forum. Such an implementation MUST implement the handover LLCP service with service name “urn:nfc:sn:handover” for exchanging the handover request/select records over NFC, and it MUST use the Bluetooth Object Push Profile for the actual Bluetooth data transfer. For legacy reasons (to remain compatible with Android 4.1 devices), the implementation SHOULD still accept SNEP GET requests for exchanging the handover request/select records over NFC. However an implementation itself SHOULD NOT send SNEP GET requests for performing connection handover.
  • [C-1-13] MUST poll for all supported technologies while in NFC discovery mode.
  • SHOULD be in NFC discovery mode while the device is awake with the screen active and the lock-screen unlocked.
  • SHOULD be capable of reading the barcode and URL (if encoded) of Thinfilm NFC Barcode products.

(Note that publicly available links are not available for the JIS, ISO, and NFC Forum specifications cited above.)

Android includes support for NFC Host Card Emulation (HCE) mode.

If device implementations include an NFC controller chipset capable of HCE (for NfcA and/or NfcB) and support Application ID (AID) routing, they:

  • [C-2-1] MUST report the android.hardware.nfc.hce feature constant.
  • [C-2-2] MUST support NFC HCE APIs as defined in the Android SDK.

If device implementations include an NFC controller chipset capable of HCE for NfcF, and implement the feature for third-party applications, they:

  • [C-3-1] MUST report the android.hardware.nfc.hcef feature constant.
  • [C-3-2] MUST implement the NfcF Card Emulation APIs as defined in the Android SDK.

If device implementations include general NFC support as described in this section and support MIFARE technologies (MIFARE Classic, MIFARE Ultralight, NDEF on MIFARE Classic) in the reader/writer role, they:

  • [C-4-1] MUST implement the corresponding Android APIs as documented by the Android SDK.
  • [C-4-2] MUST report the feature com.nxp.mifare from the android.content.pm.PackageManager.hasSystemFeature () method. Note that this is not a standard Android feature and as such does not appear as a constant in the android.content.pm.PackageManager class.

7.4.5。最低網路能力

設備實現:

  • [C-0-1] MUST include support for one or more forms of data networking. Specifically, device implementations MUST include support for at least one data standard capable of 200Kbit/sec or greater. Examples of technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g, Ethernet, Bluetooth PAN, etc.
  • [C-0-2] MUST include an IPv6 networking stack and support IPv6 communication using the managed APIs, such as java.net.Socket and java.net.URLConnection , as well as the native APIs, such as AF_INET6 sockets.
  • [C-0-3] MUST enable IPv6 by default.
  • MUST ensure that IPv6 communication is as reliable as IPv4, for example.
  • [C-0-4] MUST maintain IPv6 connectivity in doze mode.
  • [C-0-5] Rate-limiting MUST NOT cause the device to lose IPv6 connectivity on any IPv6-compliant network that uses RA lifetimes of at least 180 seconds.
  • SHOULD also include support for at least one common wireless data standard, such as 802.11 (Wi-Fi) when a physical networking standard (such as Ethernet) is the primary data connection
  • MAY implement more than one form of data connectivity.

The required level of IPv6 support depends on the network type, as follows:

If devices implementations support Wi-Fi networks, they:

  • [C-1-1] MUST support dual-stack and IPv6-only operation on Wi-Fi.

If device implementations support Ethernet networks, they:

  • [C-2-1] MUST support dual-stack operation on Ethernet.

If device implementations support cellular data, they:

  • [C-3-1] MUST simultaneously meet these requirements on each network to which it is connected when a device is simultaneously connected to more than one network (eg, Wi-Fi and cellular data), .
  • SHOULD support IPv6 operation (IPv6-only and possibly dual-stack) on cellular data.

7.4.6。同步設定

設備實現:

7.4.7.資料保護程式

If device implementations include a metered connection, they are:

  • [SR] STRONGLY RECOMMENDED to provide the data saver mode.

If device implementations provide the data saver mode, they:

如果設備實作不提供資料保護模式,它們:

  • [C-2-1] MUST return the value RESTRICT_BACKGROUND_STATUS_DISABLED for ConnectivityManager.getRestrictBackgroundStatus()
  • [C-2-2] MUST NOT broadcast ConnectivityManager.ACTION_RESTRICT_BACKGROUND_CHANGED .
  • [C-2-3] MUST have an activity that handles the Settings.ACTION_IGNORE_BACKGROUND_DATA_RESTRICTIONS_SETTINGS intent but MAY implement it as a no-op.

7.5。相機

If device implementations include at least one camera, they:

  • [C-1-1] MUST declare the android.hardware.camera.any feature flag.
  • [C-1-2] MUST be possible for an application 到 simultaneously allocate 3 RGBA_8888 bitmaps equal to the size of the images produced by the largest-resolution捕獲。

7.5.1.後置攝像頭

A rear-facing camera is a camera located on the side of the device opposite the display; that is, it images scenes on the far side of the device, like a traditional camera.

設備實現:

  • 應包括後置攝像頭。

If device implementations include at least one rear-facing camera, they:

  • [C-1-1] MUST report the feature flag android.hardware.camera and android.hardware.camera.any .
  • [C-1-2] MUST have a resolution of at least 2 megapixels.
  • SHOULD have either hardware auto-focus or software auto-focus implemented in the camera driver (transparent to application software).
  • MAY have fixed-focus or EDOF (extended depth of field) hardware.
  • 可能包括閃光燈。

如果相機配備閃光燈:

  • [C-2-1] the flash lamp MUST FLASH_MODE_AUTO be lit while an android.hardware.Camera.PreviewCallback instance has been registered on a Camera preview surface, unless the application has explicitly enabled the flash FLASH_MODE_ON on the Camera.Parameters物件。請注意,此約束不適用於裝置的內建系統相機應用程序,而僅適用於使用Camera.PreviewCallback的第三方應用程式。

7.5.2.前置鏡頭

前置相機是與顯示器位於裝置同一側的相機;也就是說,通常用於對使用者進行成像的相機,例如用於視訊會議和類似應用。

設備實現:

  • MAY include a front-facing camera.

If device implementations include at least one front-facing camera, they:

  • [C-1-1] MUST report the feature flag android.hardware.camera.any and android.hardware.camera.front .
  • [C-1-2] 解析度必須至少為 VGA(640x480 像素)。
  • [C-1-3] 不得使用前置鏡頭作為 Camera API 的預設鏡頭,也不得將 API 配置為將前置鏡頭視為預設後置鏡頭,即使它是唯一的相機在裝置上。
  • [C-1-4] The camera preview MUST be mirrored horizo​​​​ntally relative to the orientation specified by the application when the current application has explicitly requested that the Camera display be rotated via a call to the android.hardware.Camera.setDisplayOrientation() 。 Conversely, the preview MUST be mirrored along the device's default horizontal axis when the current application does not explicitly request that the Camera display be rotated via a call to the android.hardware.Camera.setDisplayOrientation() method.
  • [C-1-5] MUST NOT mirror the final captured still image or video streams returned to application callbacks or committed to media storage.
  • [C-1-6] MUST mirror the image displayed by the postview in the same manner as the camera preview image stream.
  • 可以包括後置相機可用的功能(例如自動對焦、閃光燈等),如第 7.5.1 節所述。

If device implementations are capable of being rotated by user (such as automatically via an accelerometer or manually via user input):

  • [C-2-1] The camera preview MUST be mirrored horizontally relative to the device's current orientation.

7.5.3.外接攝影機

設備實現:

  • MAY include support for an external camera that is not necessarily always connected.

If device implementations include support for an external camera, they:

  • [C-1-1] MUST declare the platform feature flag android.hardware.camera.external and android.hardware camera.any .
  • [C-1-2] MUST support USB Video Class (UVC 1.0 or higher) if the external camera connects through the USB port.
  • 應支援視訊壓縮(例如 MJPEG),以實現高品質未編碼串流(即原始或獨立壓縮的圖片流)的傳輸。
  • 可以支援多個攝影機。
  • 可以支援基於攝影機的視訊編碼。

If camera-based video encoding is supported:

  • [C-2-1] 設備實作必須可以存取同步未編碼/MJPEG 流(QVGA 或更高解析度)。

7.5.4.相機 API 行為

Android includes two API packages to access the camera, the newer android.hardware.camera2 API expose lower-level camera control to the app, including efficient zero-copy burst/streaming flows and per-frame controls of exposure, gain, white balance gains, color conversion, denoising, sharpening, and more.

The older API package, android.hardware.Camera , is marked as deprecated in Android 5.0 but as it should still be available for apps to use. Android device implementations MUST ensure the continued support of the API as described in this section and in the Android SDK.

Device implementations MUST implement the following behaviors for the camera-related APIs, for all available cameras.設備實現:

  • [C-0-1] MUST use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to application callbacks when an application has never called android.hardware.Camera.Parameters.setPreviewFormat(int) .
  • [C-0-2] MUST further be in the NV21 encoding format when an application registers an android.hardware.Camera.PreviewCallback instance and the system calls the onPreviewFrame() method and the preview format is YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() . That is, NV21 MUST be the default.
  • [C-0-3] MUST support the YV12 format (as denoted by the android.graphics.ImageFormat.YV12 constant) for camera previews for both front- and rear-facing cameras for android.hardware.Camera . (The hardware video encoder and camera may use any native pixel format, but the device implementation MUST support conversion to YV12.)
  • [C-0-4] MUST support the android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG formats as outputs through the android.media.ImageReader API for android.hardware.camera2 .
  • [C-0-5] MUST still implement the full Camera API included in the Android SDK documentation, regardless of whether the device includes hardware autofocus or other capabilities. For instance, cameras that lack autofocus MUST still call any registered android.hardware.Camera.AutoFocusCallback instances (even though this has no relevance to a non-autofocus camera.) Note that this does apply to front-facing cameras; for instance, even though most front-facing cameras do not support autofocus, the API callbacks must still be “faked” as described.
  • [C-0-6] MUST recognize and honor each parameter name defined as a constant on the android.hardware.Camera.Parameters class. Conversely, device implementations MUST NOT honor or recognize string constants passed to the android.hardware.Camera.setParameters() method other than those documented as constants on the android.hardware.Camera.Parameters .也就是說,如果硬體允許,設備實作必須支援所有標準相機參數,並且不得支援自訂相機參數類型。 For instance, device implementations that support image capture using high dynamic range (HDR) imaging techniques MUST support camera parameter Camera.SCENE_MODE_HDR .
  • [C-0-7] MUST report the proper level of support with the android.info.supportedHardwareLevel property as described in the Android SDK and report the appropriate framework feature flags .
  • [C-0-8] MUST also declare its individual camera capabilities of android.hardware.camera2 via the android.request.availableCapabilities property and declare the appropriate feature flags ; MUST define the feature flag if any of its attached camera devices supports the feature.
  • [C-0-9] MUST broadcast the Camera.ACTION_NEW_PICTURE intent whenever a new picture is taken by the camera and the entry of the picture has been added to the media store.
  • [C-0-10] MUST broadcast the Camera.ACTION_NEW_VIDEO intent whenever a new video is recorded by the camera and the entry of the picture has been added to the media store.

7.5.5。相機方向

If device implementations have a front- or a rear-facing camera, such camera(s):

  • [C-1-1] 方向必須使相機的長邊尺寸與螢幕的長邊尺寸對齊。也就是說,當設備處於橫向方向時,相機必須以橫向方向捕捉影像。無論設備的自然方向如何,這都適用;也就是說,它適用於橫向主設備以及縱向主設備。

7.6。記憶體和儲存

7.6.1.最小內存和存儲

設備實現:

  • [C-0-1] MUST include a Download Manager that applications MAY use to download data files and they MUST be capable of downloading individual files of at least 100MB in size to the default “cache” location.

7.6.2.應用程式共享儲存

設備實現:

  • [C-0-1] 必須提供由應用程式共用的存儲,通常也稱為「共用外部儲存」、「應用程式共用儲存」或透過其安裝的 Linux 路徑「/sdcard」。
  • [C-0-2] 必須配置預設安裝的共享存儲,即“開箱即用”,無論存儲是在內部存儲組件還是可移動存儲介質(例如安全數位卡插槽)上實現)。
  • [C-0-3] MUST mount the application shared storage directly on the Linux path sdcard or include a Linux symbolic link from sdcard to the actual mount point.
  • [C-0-4] MUST enforce the android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage as documented in the SDK.共享儲存否則必須透過獲得該許可的任何應用程式可寫入。

Device implementations MAY meet the above requirements using either of the following:

  • 使用者可存取的可移動存儲,例如安全數位 (SD) 卡插槽。
  • A portion of the internal (non-removable) storage as implemented in the Android Open Source Project (AOSP).

如果設備實現使用可移動儲存來滿足上述要求,則:

  • [C-1-1] 必須實作 Toast 或彈出式使用者介面,以便在插槽中沒有插入儲存媒體時警告使用者。
  • [C-1-2] 必須包含 FAT 格式的儲存媒體(例如 SD 卡),或在包裝盒和購買時提供的其他資料上標明該儲存媒體必須單獨購買。

If device implementations use a protion of the non-removable storage to satisfy the above requirements, they:

  • 應使用內部應用程式共用儲存的 AOSP 實作。
  • MAY share the storage space with the application private data.

If device implementations include multiple shared storage paths (such as both an SD card slot and shared internal storage), they:

  • [C-2-1] MUST allow only pre-installed and privileged Android applications with the WRITE_EXTERNAL_STORAGE permission to write to the secondary external storage, except when writing to their package-specific directories or within the URI returned by firing the ACTION_OPEN_DOCUMENT_TREE intent.

如果裝置實現具有支援 USB 週邊模式的 USB 端口,則:

  • [C-3-1] MUST provide a mechanism to access the data on the application shared storage from a host computer.
  • SHOULD expose content from both storage paths transparently through Android's media scanner service and android.provider.MediaStore .
  • 可以使用 USB 大容量存儲,但應該使用媒體傳輸協定來滿足此要求。

如果裝置實現具有 USB 週邊模式的 USB 連接埠並支援媒體傳輸協議,則它們:

  • SHOULD be compatible with the reference Android MTP host, Android File Transfer .
  • SHOULD report a USB device class of 0x00.
  • SHOULD report a USB interface name of 'MTP'.

7.6.3.可採用的存儲

If the device is expected to be mobile in nature unlike Television, device implementations are:

  • [SR] STRONGLY RECOMMENDED to implement the adoptable storage in a long-term stable location, since accidentally disconnecting them can cause data loss/corruption.

如果可移動儲存裝置連接埠處於長期穩定的位置,例如在電池盒或其他保護蓋內,則裝置實現為:

7.7. USB

如果裝置實現有 USB 端口,則:

  • SHOULD support USB peripheral mode and SHOULD support USB host mode.

7.7.1. USB週邊模式

如果裝置實作包含支援週邊模式的 USB 連接埠:

  • [C-1-1] The port MUST be connectable to a USB host that has a standard type-A or type-C USB port.
  • [C-1-2] MUST report the correct value of iSerialNumber in USB standard device descriptor through android.os.Build.SERIAL .
  • [C-1-3] 必須根據 Type-C 電阻器標準檢測 1.5A 和 3.0A 充電器,如果它們支援 Type-C USB,則必須偵測廣告中的變更。
  • [SR] The port SHOULD use micro-B, micro-AB or Type-C USB form factor. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases.
  • [SR] The port SHOULD be located on the bottom of the device (according to natural orientation) or enable software screen rotation for all apps (including home screen), so that the display ws correctly when the home screen the so that the display ws correctly wsen the orm. 。 Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to future platform releases.
  • [SR] SHOULD implement support to draw 1.5 A current during HS chirp and traffic as specified in the USB Battery Charging specification, revision 1.2 . Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases.
  • [SR] STRONGLY RECOMMENDED to not support proprietary charging methods that modify Vbus voltage beyond default levels, or alter sink/source roles as such may result in interoperability issues with the chargers or devices that support the standard USB Power Delivery methods. While this is called out as "STRONGLY RECOMMENDED", in future Android versions we might REQUIRE all type-C devices to support full interoperability with standard type-C chargers.
  • [SR] STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping when they support Type-C USB and USB host mode.
  • SHOULD support Power Delivery for high-voltage charging and support for Alternate Modes such as display out.
  • SHOULD implement the Android Open Accessory (AOA) API and specification as documented in the Android SDK documentation.

If device implementations including a USB port, implement the AOA specification, they:

  • [C-2-1] MUST declare support for the hardware feature android.hardware.usb.accessory .
  • [C-2-2] The USB mass storage class MUST include the string "android" at the end of the interface description iInterface string of the USB mass storage
  • 不應實作 Android 開放附件協定 2.0 文件中記錄的AOAv2 音訊。自 Android 版本 8.0(API 等級 26)起,AOAv2 音訊已棄用。

7.7.2. USB主機模式

如果設備實作包括支援主機模式的 USB 端口,則:

  • [C-1-1] MUST implement the Android USB host API as documented in the Android SDK and MUST declare support for the hardware feature android.hardware.usb.host .
  • [C-1-2] 必須實現對連接標準 USB 週邊裝置的支持,換句話說,它們必須:
    • 擁有裝置上的 C 型連接埠或隨附將裝置上的專有連接埠適配為標準 USB C 型連接埠(USB C 型裝置)的連接線。
    • 擁有裝置上的 A 型連接埠或隨附將裝置上的專有連接埠適配為標準 USB A 型連接埠的連接線。
    • Have an on-device micro-AB port, which SHOULD ship with a cable adapting to a standard type-A port.
  • [C-1-3] MUST NOT ship with an adapter converting from USB type A or micro-AB ports to a type-C port (receptacle).
  • [SR] STRONGLY RECOMMENDED to implement the USB audio class as documented in the Android SDK documentation.
  • SHOULD support charging the connected USB peripheral device while in host mode; advertising a source current of at least 1.5A as specified in the Termination Parameters section of the USB Type-C Cable and Connector Specification Revision 1.2 for USB Type-C connectors or using Charging Downstream Port(CDP) output current range as specified in the USB Battery Charging specifications, revision 1.2 for Micro-AB connectors.
  • 應實施並支援 USB Type-C 標準。

If device implementations include a USB port supporting host mode and the USB audio class, they:

  • [C-2-1] 必須支援USB HID 類別
  • [C-2-2] MUST support the detection and mapping of the following HID data fields specified in the USB HID Usage Tables and the Voice Command Usage Request to the KeyEvent constants as below:
    • Usage Page (0xC) Usage ID (0x0CD): KEYCODE_MEDIA_PLAY_PAUSE
    • Usage Page (0xC) Usage ID (0x0E9): KEYCODE_VOLUME_UP
    • Usage Page (0xC) Usage ID (0x0EA): KEYCODE_VOLUME_DOWN
    • Usage Page (0xC) Usage ID (0x0CF): KEYCODE_VOICE_ASSIST

如果裝置實作包括支援主機模式和儲存存取框架 (SAF) 的 USB 端口,則它們:

  • [C-3-1] MUST recognize any remotely connected MTP (Media Transfer Protocol) devices and make their contents accessible through the ACTION_GET_CONTENT , ACTION_OPEN_DOCUMENT , and ACTION_CREATE_DOCUMENT intents. 。

If device implementations include a USB port supporting host mode and USB Type-C, they:

  • [C-4-1] 必須實作 USB Type-C 規格(第 4.5.1.3.3 節)定義的雙重角色連接埠功能。
  • [SR] STRONGLY RECOMMENDED to support DisplayPort, SHOULD support USB SuperSpeed Data Rates, and are STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping.
  • [SR] STRONGLY RECOMMENDED to NOT support Audio Adapter Accessory Mode as described in the Appendix A of the USB Type-C Cable and Connector Specification Revision 1.2 .
  • SHOULD implement the Try.* model that is most appropriate for the device form factor. For example a handheld device SHOULD implement the Try.SNK model.

7.8。聲音的

7.8.1.麥克風

如果裝置實作包含麥克風,則:

  • [C-1-1] MUST report the android.hardware.microphone feature constant.
  • [C-1-2] 必須符合第 5.4 節的錄音要求。
  • [C-1-3] MUST meet the audio latency requirements in section 5.6 .
  • [SR] Are STRONGLY RECOMMENDED to support near-ultrasound recording as described in section 7.8.3 .

If device implementations omit a microphone, they:

  • [C-2-1] MUST NOT report the android.hardware.microphone feature constant.
  • [C-2-2] MUST implement the audio recording API at least as no-ops, per section 7 .

7.8.2.音訊輸出

If device implementations include a speaker or an audio/multimedia output port for an audio output peripheral such as a 4 conductor 3.5mm audio jack or USB host mode port using USB audio class , they:

  • [C-1-1] MUST report the android.hardware.audio.output feature constant.
  • [C-1-2] MUST meet the audio playback requirements in section 5.5 .
  • [C-1-3] MUST meet the audio latency requirements in section 5.6 .
  • [SR] STRONGLY RECOMMENDED to support near-ultrasound playback as described in section 7.8.3 .

如果設備實現不包括揚聲器或音訊輸出端口,則:

  • [C-2-1] MUST NOT report the android.hardware.audio output feature.
  • [C-2-2] 必須至少將音訊輸出相關 API 實作為無操作。

就本節而言,「輸出埠」是指實體接口,例如 3.5 公釐音訊插孔、HDMI 或具有 USB 音訊類別的 USB 主機模式連接埠。對透過基於無線電的協定(例如藍牙、WiFi 或蜂窩網路)的音訊輸出的支援不屬於包含「輸出連接埠」的資格。

7.8.2.1.類比音訊連接埠

In order to be compatible with the headsets and other audio accessories using the 3.5mm audio plug across the Android ecosystem, if a device implementation includes one or more analog audio ports, at least one of the audio port(s) SHOULD be a 4 conductor 3.5mm audio jack.

If device implementations have a 4 conductor 3.5mm audio jack, they:

  • [C-1-1] 必須支援透過立體聲耳機和帶麥克風的立體聲耳機播放音訊。
  • [C-1-2] MUST support TRRS audio plugs with the CTIA pin-out order.
  • [C-1-3] MUST support the detection and mapping to the keycodes for the following 3 ranges of equivalent impedance between the microphone and ground conductors on the audio plug:
    • 70 ohm or less : KEYCODE_HEADSETHOOK
    • 210-290 ohm : KEYCODE_VOLUME_UP
    • 360-680 ohm : KEYCODE_VOLUME_DOWN
  • [C-1-4] MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all contacts on plug are touching their relevant segments on the jack.
  • [C-1-5] 必須能夠在 32 歐姆揚聲器阻抗上驅動至少 150mV ± 10% 的輸出電壓。
  • [C-1-6] MUST have a microphone bias voltage between 1.8V ~ 2.9V.
  • [SR] STRONGLY RECOMMENDED to detect and map to the keycode for the following range of equivalent impedance between the microphone and ground conductors on the audio plug:
    • 110-180 ohm: KEYCODE_VOICE_ASSIST
  • SHOULD support audio plugs with the OMTP pin-out order.
  • SHOULD support audio recording from stereo headsets with a microphone.

If device implementations have a 4 conductor 3.5mm audio jack and support a microphone, and broadcast the android.intent.action.HEADSET_PLUG with the extra value microphone set as 1, they:

  • [C-2-1] 必須支援偵測插入的音訊配件上的麥克風。

7.8.3。 Near-Ultrasound

近超音波音訊的頻段為 18.5 kHz 至 20 kHz。

設備實現:

If PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND is "true", the following requirements MUST be met by the VOICE_RECOGNITION and UNPROCESSED audio sources:

  • [C-1-1] The microphone's mean power response in the 18.5 kHz to 20 kHz band MUST be no more than 15 dB below the response at 2 kHz.
  • [C-1-2] The microphone's unweighted signal to noise ratio over 18.5 kHz to 20 kHz for a 19 kHz tone at -26 dBFS MUST be no lower than 50 dB.

If PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND is "true":

  • [C-2-1] The speaker's mean response in 18.5 kHz - 20 kHz MUST be no lower than 40 dB below the response at 2 kHz.

7.9。虛擬實境

Android 包含用於建立「虛擬實境」(VR) 應用程式(包括高品質行動 VR 體驗)的 API 和工具。設備實作必須正確實作這些 API 和行為,如本節所述。

7.9.1.虛擬實境模式

Android 支援VR 模式,可在 VR 應用程式具有使用者焦點時處理通知的立體渲染並停用單眼系統 UI 元件。

7.9.2. Virtual Reality High Performance

If device implementations identify the support of high performance VR for longer user periods through the android.hardware.vr.high_performance feature flag, they:

  • [C-1-1] MUST have at least 2 physical cores.
  • [C-1-2] MUST declare android.software.vr.mode feature .
  • [C-1-3] MUST support sustained performance mode.
  • [C-1-4] MUST support OpenGL ES 3.2.
  • [C-1-5] MUST support Vulkan Hardware Level 0 and SHOULD support Vulkan Hardware Level 1.
  • [C-1-6] MUST implement EGL_KHR_mutable_render_buffer , EGL_ANDROID_front_buffer_auto_refresh , EGL_ANDROID_get_native_client_buffer , EGL_KHR_fence_sync , EGL_KHR_wait_sync , EGL_IMG_context_priority , EGL_EXT_protected_content , and expose the extensions in the list of available EGL extensions.
  • [C-1-7] GPU 和顯示器必須能夠同步對共享前端緩衝區的訪問,以便在兩個渲染上下文中以60fps 的速度進行VR 內容的交替眼渲染,並且不會出現明顯的撕裂偽影。
  • [C-1-8] MUST implement GL_EXT_multisampled_render_to_texture , GL_OVR_multiview , GL_OVR_multiview2 , GL_OVR_multiview_multisampled_render_to_texture , GL_EXT_protected_textures , and expose the extensions in the list of available GL extensions.
  • [C-1-9] MUST implement support for AHardwareBuffer flags AHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER and AHARDWAREBUFFER_USAGE_SENSOR_DIRECT_DATA as described in the NDK.
  • [C-1-10] MUST implement support for AHardwareBuffers with more than one layer.
  • [C-1-11] MUST support H.264 decoding at least 3840x2160@30fps-40Mbps (equivalent to 4 instances of 1920x1080@30fps-10Mbps or 2 instances of 1920x1080@60fps-20Mbps).
  • [C-1-12] MUST support HEVC and VP9, MUST be capable to decode at least 1920x1080@30fps-10Mbps and SHOULD be capable to decode 3840x2160@30fps-20Mbps (equivalent to 4 instances of 1920x1080@30fps-5Mbps).
  • [C-1-13] MUST support HardwarePropertiesManager.getDeviceTemperatures API and return accurate values for skin temperature.
  • [C-1-14] MUST have an embedded screen, and its resolution MUST be at least be FullHD(1080p) and STRONGLY RECOMMENDED TO BE be QuadHD (1440p) or higher.
  • [C-1-15] The display MUST update at least 60 Hz while in VR Mode.
  • [C-1-16] The display latency on Gray-to-Gray, White-to-Black, and Black-to-White switching time MUST be ≤ 3 ms.
  • [C-1-17] The display MUST support a low-persistence mode with ≤5 ms persistence, persistence being defined as the amount of time for which a pixel is emitting light.
  • [C-1-18] 必須支援藍牙 4.2 和藍牙 LE 資料長度擴展第 7.4.3 節
  • [SR] STRONGLY RECOMMENDED to support android.hardware.sensor.hifi_sensors feature and MUST meet the gyroscope, accelerometer, and magnetometer related requirements for android.hardware.hifi_sensors .
  • MAY provide an exclusive core to the foreground application and MAY support the Process.getExclusiveCores API to return the numbers of the cpu cores that are exclusive to the top foreground application.

如果支援獨佔核心,則該核心:

  • [C-2-1] 不得允許任何其他用戶空間進程在其上運行(應用程式使用的裝置驅動程式除外),但可以允許某些核心進程在必要時運行。

8. 性能和功率

Some minimum performance and power criteria are critical to the user experience and impact the baseline assumptions developers would have when developing an app.

8.1.使用者體驗一致性

A smooth user interface can be provided to the end user if there are certain minimum requirements to ensure a consistent frame rate and response times for applications and games. Device implementations, depending on the device type, MAY have measurable requirements for the user interface latency and task switching as described in section 2 .

8.2.文件 I/O 存取效能

Providing a common baseline for a consistent file access performance on the application private data storage ( /data partition) allows app developers to set a proper expectation that would help their software design. Device implementations, depending on the device type, MAY have certain requirements described in section 2 for the following read and write operations:

  • Sequential write performance . Measured by writing a 256MB file using 10MB write buffer.
  • 隨機寫入效能。透過使用 4KB 寫入緩衝區寫入 256MB 檔案來測量。
  • 順序讀取效能。透過使用 10MB 寫入緩衝區讀取 256MB 檔案來測量。
  • 隨機讀取效能。透過使用 4KB 寫入緩衝區讀取 256MB 檔案來測量。

8.3.省電模式

Android includes App Standby and Doze power-saving modes to optimize battery usage. [SR] All Apps exempted from these modes are STRONGLY RECOMMENDED to be made visible to the end user. [SR] The triggering, maintenance, wakeup algorithms and the use of global system settings of these power-saving modes are STRONGLY RECOMMENDED NOT to deviate from the Android Open Source Project.

除了省電模式之外,Android 裝置實作還可以實現進階配置和電源介面 (ACPI) 定義的任意或全部 4 種睡眠電源狀態。

If device implementations implements S3 and S4 power states as defined by the ACPI, they:

  • [C-1-1] MUST only enter these states when closing a lid that is physically part of the device.

8.4.用電核算

A more accurate accounting and reporting of the power consumption provides the app developer both the incentives and the tools to optimize the power usage pattern of the application.

設備實現:

  • [SR] STRONGLY RECOMMENDED to provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site.
  • [SR] STRONGLY RECOMMENDED to report all power consumption values in milliampere hours (mAh).
  • [SR] STRONGLY RECOMMENDED to report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the uid_cputime kernel module implementation.
  • [SR] STRONGLY RECOMMENDED to make this power usage available via the adb shell dumpsys batterystats shell command to the app developer.
  • SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.

8.5。一致的性能

Performance can fluctuate dramatically for high-performance long-running apps, either because of the other apps running in the background or the CPU throttling due to temperature limits. Android includes programmatic interfaces so that when the device is capable, the top foreground application can request that the system optimize the allocation of the resources to address such fluctuations.

設備實現:

If device implementations report support of Sustained Performance Mode, they:

  • [C-1-1] MUST provide the top foreground application a consistent level of performance for at least 30 minutes, when the app requests it.
  • [C-1-2] MUST honor the Window.setSustainedPerformanceMode() API and other related APIs.

If device implementations include two or more CPU cores, they:

  • SHOULD provide at least one exclusive core that can be reserved by the top foreground application.

If device implementations support reserving one exclusive core for the top foreground application, they:

  • [C-2-1] MUST report through the Process.getExclusiveCores() API method the ID numbers of the exclusive cores that can be reserved by the top foreground application.
  • [C-2-2] MUST not allow any user space processes except the device drivers used by the application to run on the exclusive cores, but MAY allow some kernel processes to run as necessary.

If device implementations do not support an exclusive core, they:

9. 安全模型相容性

設備實現:

  • [C-0-1] MUST implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs in the Android developer documentation.

  • [C-0-2] MUST support installation of self-signed applications without requiring any additional permissions/certificates from any third parties/authorities. Specifically, compatible devices MUST support the security mechanisms described in the follow subsections.

9.1.權限

設備實現:

  • [C-0-1] MUST support the Android permissions model as defined in the Android developer documentation. Specifically, they MUST enforce each permission defined as described in the SDK documentation;無法省略,更改或忽略權限。

  • MAY add additional permissions, provided the new permission ID strings are not in the android.\* namespace.

  • [C-0-2] Permissions with a protectionLevel of PROTECTION_FLAG_PRIVILEGED MUST only be granted to apps preloaded in the privileged path(s) of the system image and within the subset of the explicitly allowlisted permissions for each app. The AOSP implementation meets this requirement by reading and honoring the allowlisted permissions for each app from the files in the etc/permissions/ path and using the system/priv-app path as the privileged path.

Permissions with a protection level of dangerous are runtime permissions. Applications with targetSdkVersion > 22 request them at runtime.

設備實現:

  • [C-0-3] MUST show a dedicated interface for the user to decide whether to grant the requested runtime permissions and also provide an interface for the user to manage runtime permissions.
  • [C-0-4] MUST have one and only one implementation of both user interfaces.
  • [C-0-5] MUST NOT grant any runtime permissions to preinstalled apps unless:
  • the user's consent can be obtained before the application uses it
  • the runtime permissions are associated with an intent pattern for which the preinstalled application is set as the default handler

If device implementations include a pre-installed app or wish to allow third-party apps to access the usage statistics, they:

  • [SR] are STRONGLY RECOMMENDED provide user-accessible mechanism to grant or revoke access to the usage stats in response to the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent for apps that declare the android.permission.PACKAGE_USAGE_STATS permission.

如果設備實現打算禁止任何應用程式(包括預先安裝的應用程式)存取使用情況統計信息,則:

  • [C-1-1] MUST still have an activity that handles the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent pattern but MUST implement it as a no-op, that is to have an equivalent behavior as when the user is declined for access.

9.2. UID 和進程隔離

設備實現:

  • [C-0-1] MUST support the Android application sandbox model, in which each application runs as a unique Unixstyle UID and in a separate process.
  • [C-0-2] MUST support running multiple applications as the same Linux user ID, provided that the applications are properly signed and constructed, as defined in the Security and Permissions reference .

9.3.檔案系統權限

設備實現:

9.4.備用執行環境

Device implementations MUST keep consistency of the Android security and permission model, even if they include runtime environments that execute applications using some other software or technology than the Dalvik Executable Format or native code.換句話說:

  • [C-0-1] Alternate runtimes MUST themselves be Android applications, and abide by the standard Android security model, as described elsewhere in section 9 .

  • [C-0-2] Alternate runtimes MUST NOT be granted access to resources protected by permissions not requested in the runtime's AndroidManifest.xml file via the < uses-permission > mechanism.

  • [C-0-3] Alternate runtimes MUST NOT permit applications to make use of features protected by Android permissions restricted to system applications.

  • [C-0-4] Alternate runtimes MUST abide by the Android sandbox model and installed applications using an alternate runtime MUST NOT reuse the sandbox of any other app installed on the device, exception the sandbox of any other app installed on the device, exceptalough the standard 。

  • [C-0-5] Alternate runtimes MUST NOT launch with, grant, or be granted access to the sandboxes corresponding to other Android applications.

  • [C-0-6] Alternate runtimes MUST NOT be launched with, be granted, or grant to other applications any privileges of the superuser (root), or of any other user ID.

  • [C-0-7] When the .apk files of alternate runtimes are included in the system image of device implementations, it MUST be signed with a key distinct from the key used to sign other applications included with the device implementations.

  • [C-0-8] When installing applications, alternate runtimes MUST obtain user consent for the Android permissions used by the application.

  • [C-0-9] When an application needs to make use of a device resource for which there is a corresponding Android permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the user that the application will be able to access that resource.

  • [C-0-10] When the runtime environment does not record application capabilities in this manner, the runtime environment MUST list all permissions held by the runtime itself when installing any application using that runtime.

  • Alternate runtimes SHOULD install apps via the PackageManager into separate Android sandboxes (Linux user IDs, etc.).

  • 替代運行時可能會使用替代運行時提供所有應用程式共享的單一Android沙箱。

9.5。多用戶支援

Android includes support for multiple users and provides support for full user isolation.

  • Device implementations MAY but SHOULD NOT enable multi-user if they use removable media for primary external storage.

If device implementations include multiple users, they:

  • [C-1-1] MUST meet the following requirements related to multi-user support .
  • [C-1-2] MUST, for each user, implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs.
  • [C-1-3] MUST have separate and isolated shared application storage (aka /sdcard ) directories for each user instance.
  • [C-1-4] MUST ensure that applications owned by and running on behalf a given user cannot list, read, or write to the files owned by any other user, even if the data of both users are stored on the or文件系統。
  • [C-1-5] MUST encrypt the contents of the SD card when multiuser is enabled using a key stored only on non-removable media accessible only to the system if device implementations use removable media for the external storage APIs. As this will make the media unreadable by a host PC, device implementations will be required to switch to MTP or a similar system to provide host PCs with access to the current user's data.

If device implementations include multiple users and do not declare the android.hardware.telephony feature flag, they:

  • [C-2-1] MUST support restricted profiles, a feature that allows device owners to manage additional users and their capabilities on the device. With restricted profiles, device owners can quickly set up separate environments for additional users to work in, with the ability to manage finer-grained restrictions in the apps that are available in those environments.

If device implementations include multiple users and declare the android.hardware.telephony feature flag, they:

  • [C-3-1] MUST NOT support restricted profiles but MUST align with the AOSP implementation of controls to enable /disable other users from accessing the voice calls and SMS.

9.6.高級簡訊警告

Android includes support for warning users of any outgoing premium SMS message . Premium SMS messages are text messages sent to a service registered with a carrier that may incur a charge to the user.

If device implementations declare support for android.hardware.telephony , they:

  • [C-1-1] MUST warn users before sending a SMS message to numbers identified by regular expressions defined in /data/misc/sms/codes.xml file in the device. The upstream Android Open Source Project provides an implementation that satisfies this requirement.

9.7.核心安全特性

The Android Sandbox includes features that use the Security-Enhanced Linux (SELinux) mandatory access control (MAC) system, seccomp sandboxing, and other security features in the Linux kernel.設備實現:

  • [C-0-1] MUST maintain compatibility with existing applications, even when SELinux or any other security features are implemented below the Android framework.
  • [C-0-2] MUST NOT have a visible user interface when a security violation is detected and successfully blocked by the security feature implemented below the Android fr時開發。
  • [C-0-3] MUST NOT make SELinux or any other security features implemented below the Android framework configurable to the user or app developer.
  • [C-0-4] MUST NOT allow an application that can affect another application through an API (such as a Device Administration API) to configure a policy that breaks compatibility.
  • [C-0-5] MUST split the media framework into multiple processes so that it is possible to more narrowly grant access for each process as described in the Android Open Source Project site.
  • [C-0-6] MUST implement a kernel application sandboxing mechanism which allows filtering of system calls using a configurable policy from multithreaded programs. The upstream Android Open Source Project meets this requirement through enabling the seccomp-BPF with threadgroup synchronization (TSYNC) as described in the Kernel Configuration section of source.android.com .

Kernel integrity and self-protection features are integral to Android security.設備實現:

  • [C-0-7] MUST implement kernel stack buffer overflow protection mechanisms. Examples of such mechanisms are CC_STACKPROTECTOR_REGULAR and CONFIG_CC_STACKPROTECTOR_STRONG .
  • [C-0-8] MUST implement strict kernel memory protections where executable code is read-only, read-only data is non-executable and non-writable, and writable data is non-executable (eg CONFIG_DEBUG_RODATA or CONFIG_STRICT_KERNEL_RWX ).
  • [SR] STRONGLY RECOMMENDED to keep kernel data which is written only during initialization marked read-only after initialization (eg __ro_after_init ).
  • [SR} STRONGLY RECOMMENDED to implement static and dynamic object size bounds checking of copies between user-space and kernel-space (eg CONFIG_HARDENED_USERCOPY ).
  • [SR] STRONGLY RECOMMENDED to never execute user-space memory when running in the kernel (eg hardware PXN, or emulated via CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_ARM64_SW_TTBR0_PAN ).
  • [SR] STRONGLY RECOMMENDED to never read or write user-space memory in the kernel outside of normal usercopy access APIs (eg hardware PAN, or emulated via CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_ARM64_SW_TTBR0_PAN ).
  • [SR] STRONGLY RECOMMENDED to randomize the layout of the kernel code and memory, and to avoid exposures that would compromise the randomization (eg CONFIG_RANDOMIZE_BASE with bootloader entropy via the /chosen/kaslr-seed Device Tree node or EFI_RNG_PROTOCOL ).

If device implementations use a Linux kernel, they:

  • [C-1-1] MUST implement SELinux.
  • [C-1-2] MUST set SELinux to global enforcing mode.
  • [C-1-3] MUST configure all domains in enforcing mode. No permissive mode domains are allowed, including domains specific to a device/vendor.
  • [C-1-4] MUST NOT modify, omit, or replace the neverallow rules present within the system/sepolicy folder provided in the upstream Android Open Source Project (AOSP) and the policy MUST compile with all neverallow rules present, for both AOSP SELinux domains as well as device/vendor specific domains.
  • SHOULD retain the default SELinux policy provided in the system/sepolicy folder of the upstream Android Open Source Project and only further add to this policy for their own device-specific configuration.

If device implementations use kernel other than Linux, they:

  • [C-2-1] MUST use an mandatory access control system that is equivalent to SELinux.

9.8.隱私

9.8.1.使用歷史

Android stores the history of the user's choices and manages such history by UsageStatsManager .

設備實現:

  • [C-0-1] MUST keep a reasonable retention period of such user history.
  • [SR] Are STRONGLY RECOMMENDED to keep the 14 days retention period as configured by default in the AOSP implementation.

9.8.2.記錄

If device implementations include functionality in the system that captures the contents displayed on the screen and/or records the audio stream played on the device, they:

  • [C-1-1] MUST have an ongoing notification to the user whenever this functionality is enabled and actively capturing/recording.

If device implementations include a component enabled out-of-box, capable of recording ambient audio to infer useful information about user's context, they:

  • [C-2-1] MUST NOT store in persistent on-device storage or transmit off the device the recorded raw audio or any format that can be converted back into the original audio or a near facsimile, except with explicit user consent.

9.8.3。連接性

如果裝置實現具有支援 USB 週邊模式的 USB 端口,則:

  • [C-1-1] MUST present a user interface asking for the user's consent before allowing access to the contents of the shared storage over the USB port.

9.8.4。網路流量

設備實現:

  • [C-0-1] MUST preinstall the same root certificates for the system-trusted Certificate Authority (CA) store as provided in the upstream Android Open Source Project.
  • [C-0-2] MUST ship with an empty user root CA store.
  • [C-0-3] MUST display a warning to the user indicating the network traffic may be monitored, when a user root CA is added.

If device traffic is routed through a VPN, device implementations:

  • [C-1-1] MUST display a warning to the user indicating either:
    • That network traffic may be monitored.
    • That network traffic is being routed through the specific VPN application providing the VPN.

If device implementations have a mechanism, enabled out-of-box by default, that routes network data traffic through a proxy server or VPN gateway (for example, preloading a VPN service with android.permission.CONTROL_VPN granted), they:

  • [C-2-1] MUST ask for the user's consent before enabling that mechanism, unless that VPN is enabled by the Device Policy Controller via the DevicePolicyManager.setAlwaysOnVpnPackage() , in which case the user does not need to provide a separate consent, but MUST only be notified.

9.9.資料儲存加密

If device implementations support a secure lock screen as described in section 9.11.1 , they:

  • [C-1-1] MUST support data storage encryption of the application private data ( /data partition ), as well as the application shared storage partition ( /sdcard partition ) if it is a permanent, non-removable part of the device.

If device implementations support a secure lock screen as described in section 9.11.1 and support data storage encryption with Advanced Encryption Standard (AES) crypto performance above 50MiB/sec, they:

  • [C-2-1] MUST enable the data storage encryption by default at the time the user has completed the out-of-box setup experience. If device implementations are already launched on an earlier Android version with encryption disabled by default, such a device cannot meet the requirement through a system software update and thus MAY be exempted.

  • SHOULD meet the above data storage encryption requirement via implementing File Based Encryption (FBE).

9.9.1. Direct Boot

設備實現:

  • [C-0-1] MUST implement the Direct Boot mode APIs even if they do not support Storage Encryption.

  • [C-0-2] The ACTION_LOCKED_BOOT_COMPLETED and ACTION_USER_UNLOCKED Intents MUST still be broadcast to signal Direct Boot aware applications that Device Encrypted (DE) and Credential Encrypted (CE) storage locations are available for user.

9.9.2.基於文件的加密

If device implementations support FBE, they:

  • [C-1-1] MUST boot up without challenging the user for credentials and allow Direct Boot aware apps to access to the Device Encrypted (DE) storage after the ACTION_LOCKED_BOOT_COMPLETED message is broadcasted.
  • [C-1-2] MUST only allow access to Credential Encrypted (CE) storage after the user has unlocked the device by supplying their credentials (eg. passcode, pin, pattern or fingerprint) and the ACTION_USER_UNLOCKED message is broadcasted.
  • [C-1-3] MUST NOT offer any method to unlock the CE protected storage without the user-supplied credentials.
  • [C-1-4] MUST support Verified Boot and ensure that DE keys are cryptographically bound to the device's hardware root of trust.
  • [C-1-5] MUST support encrypting file contents using AES with a key length of 256-bits in XTS mode.
  • [C-1-6] MUST support encrypting file name using AES with a key length of 256-bits in CBC-CTS mode.

  • The keys protecting CE and DE storage areas:

  • [C-1-7] MUST be cryptographically bound to a hardware-backed Keystore.

  • [C-1-8] CE keys MUST be bound to a user's lock screen credentials.
  • [C-1-9] CE keys MUST be bound to a default passcode when the user has not specified lock screen credentials.
  • [C-1-10] MUST be unique and distinct, in other words no user's CE or DE key matches any other user's CE or DE keys.

  • [C-1-11] MUST use the mandatorily supported ciphers, key lengths and modes by default.

  • SHOULD make preloaded essential apps (eg Alarm, Phone, Messenger) Direct Boot aware.

  • MAY support alternative ciphers, key lengths and modes for file content and file name encryption.

The upstream Android Open Source project provides a preferred implementation of this feature based on the Linux kernel ext4 encryption feature.

9.9.3。全碟加密

If device implementations support full disk encryption (FDE), they:

  • [C-1-1] MUST use AES with a key of 128-bits (or greater) and a mode designed for storage (for example, AES-XTS, AES-CBC-ESSIV).
  • [C-1-2] MUST use a default passcode to wrap the encryption key and MUST NOT write the encryption key to storage at any time without being encrypted.
  • [C-1-3] MUST provide the user the possibility to AES encrypt the encryption key, except when it is in active use, with the lock screen credentials stretched using a slow stretching algorithm (eg PBKDF2 or scrypt).
  • [C-1-4] The above default password stretching algorithm MUST be cryptographically bound to that keystore when the user has not specified a lock screen credentials or has disabled use of the passcode for encryption and the device provides a hardware-backed keystore.
  • [C-1-5] MUST NOT send encryption key off the device (even when wrapped with the user passcode and/or hardware bound key).

The upstream Android Open Source project provides a preferred implementation of this feature, based on the Linux kernel feature dm-crypt.

9.10。 Device Integrity

The following requirements ensures there is transparency to the status of the device integrity.設備實現:

  • [C-0-1] MUST correctly report through the System API method PersistentDataBlockManager.getFlashLockState() whether their bootloader state permits flashing of the system image. The FLASH_LOCK_UNKNOWN state is reserved for device implementations upgrading from an earlier version of Android where this new system API method did not exist.

Verified boot is a feature that guarantees the integrity of the device software. If a device implementation supports the feature, it:

  • [C-1-1] MUST declare the platform feature flag android.software.verified_boot .
  • [C-1-2] MUST perform verification on every boot sequence.
  • [C-1-3] MUST start verification from an immutable hardware key that is the root of trust and go all the way up to the system partition.
  • [C-1-4] MUST implement each stage of verification to check the integrity and authenticity of all the bytes in the next stage before executing the code in the next stage.
  • [C-1-5] MUST use verification algorithms as strong as current recommendations from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048).
  • [C-1-6] MUST NOT allow boot to complete when system verification fails, unless the user consents to attempt booting anyway, in which case the data from any non-verified storage blocks MUST not be used.
  • [C-1-7] MUST NOT allow verified partitions on the device to be modified unless the user has explicitly unlocked the boot loader.
  • [SR] If there are multiple discrete chips in the device (eg radio, specialized image processor), the boot process of each of those chips is STRONGLY RECOMMENDED to verify every stage upon booting.
  • [SR] STRONGLY RECOMMENDED to use tamper-evident storage: for when the bootloader is unlocked. Tamper-evident storage means that the boot loader can detect if the storage has been tampered with from inside the HLOS (High Level Operating System).
  • [SR] STRONGLY RECOMMENDED to prompt the user, while using the device, and require physical confirmation before allowing a transition from boot loader locked mode to boot loader unlocked mode.
  • [SR] STRONGLY RECOMMENDED to implement rollback protection for the HLOS (eg boot, system partitions) and to use tamper-evident storage for storing the metadata used for determining the minimum allowable OS version.
  • SHOULD implement rollback protection for any component with persistent firmware (eg modem, camera) and SHOULD use tamper-evident storage for storing the metadata used for determining the minimum allowable version.

The upstream Android Open Source Project provides a preferred implementation of this feature in the external/avb/ repository, which can be integrated into the boot loader used for loading Android.

Device implementations with Advanced Encryption Standard (AES) crypto performance above 50 MiB/seconds:

  • [C-2-1] MUST support verified boot for device integrity.

If a device implementation is already launched without supporting verified boot on an earlier version of Android, such a device can not add support for this feature with a system software update and thus are exempted from the requirement.

9.11。 Keys and Credentials

The Android Keystore System allows app developers to store cryptographic keys in a container and use them in cryptographic operations through the KeyChain API or the Keystore API .設備實現:

  • [C-0-1] MUST at least allow more than 8,192 keys to be imported.
  • [C-0-2] The lock screen authentication MUST rate-limit attempts and MUST have an exponential backoff algorithm. Beyond 150 failed attempts, the delay MUST be at least 24 hours per attempt.
  • SHOULD not limit the number of keys that can be generated

When the device implementation supports a secure lock screen, it:

  • [C-1-1] MUST back up the keystore implementation with secure hardware.
  • [C-1-2] MUST have implementations of RSA, AES, ECDSA and HMAC cryptographic algorithms and MD5, SHA1, and SHA-2 family hash functions to properly support the Android Keystore system's supported algorithms in an area that is securely isolated from the code running on the kernel and above. Secure isolation MUST block all potential mechanisms by which kernel or userspace code might access the internal state of the isolated environment, including DMA. The upstream Android Open Source Project (AOSP) meets this requirement by using the Trusty implementation, but another ARM TrustZone-based solution or a third-party reviewed secure implementation of a proper hypervisor-based isolation are alternative options.
  • [C-1-3] MUST perform the lock screen authentication in the isolated execution environment and only when successful, allow the authentication-bound keys to be used. The upstream Android Open Source Project provides the Gatekeeper Hardware Abstraction Layer (HAL) and Trusty, which can be used to satisfy this requirement.
  • [C-1-4] MUST support key attestation where the attestation signing key is protected by secure hardware and signing is performed in secure hardware. The attestation signing keys MUST be shared across large enough number of devices to prevent the keys from being used as device identifiers. One way of meeting this requirement is to share the same attestation key unless at least 100,000 units of a given SKU are produced. If more than 100,000 units of an SKU are produced, a different key MAY be used for each 100,000 units.

Note that if a device implementation is already launched on an earlier Android version, such a device is exempted from the requirement to have a hardware-backed keystore and support the key attestation, unless it declares the android.hardware.fingerprint feature which requires a hardware-backed keystore.

9.11.1. Secure Lock Screen

If device implementations have a secure lock screen and include one or more trust agent, which implements the TrustAgentService System API, then they:

  • [C-1-1] MUST indicate the user in the Settings and Lock screen user interface of situations where either the screen auto-lock is deferred or the screen lock can be unlocked by the trust agent. The AOSP meets the requirement by showing a text description for the "Automatically lock setting" and "Power button instantly locks setting" menus and a distinguishable icon on the lock screen.
  • [C-1-2] MUST respect and fully implement all trust agent APIs in the DevicePolicyManager class, such as the KEYGUARD_DISABLE_TRUST_AGENTS constant.
  • [C-1-3] MUST NOT fully implement the TrustAgentService.addEscrowToken() function on a device that is used as the primary personal device (eg handheld) but MAY fully implement the function on device implementations typically shared.
  • [C-1-4] MUST encrypt the tokens added by TrustAgentService.addEscrowToken() before storing them on the device.
  • [C-1-5] MUST NOT store the encryption key on the device.
  • [C-1-6] MUST inform the user about the security implications before enabling the escrow token to decrypt the data storage.

If device implementations add or modify the authentication methods to unlock the lock screen, then for such an authentication method to be treated as a secure way to lock the screen, they:

If device implementations add or modify the authentication methods to unlock the lock screen if based on a known secret then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-3-1] The entropy of the shortest allowed length of inputs MUST be greater than 10 bits.
  • [C-3-2] The maximum entropy of all possible inputs MUST be greater than 18 bits.
  • [C-3-3] MUST not replace any of the existing authentication methods (PIN,pattern, password) implemented and provided in AOSP.
  • [C-3-4] MUST be disabled when the Device Policy Controller (DPC) application has set the password quality policy via the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_SOMETHING .

If device implementations add or modify the authentication methods to unlock the lock screen if based on a physical token or the location, then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-4-1] MUST have a fall-back mechanism to use one of the primary authentication methods which is based on a known secret and meets the requirements to be treated as a secure lock screen.
  • [C-4-2] MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the policy with either the DevicePolicyManager.setKeyguardDisabledFeatures(KEYGUARD_DISABLE_TRUST_AGENTS) method or the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_UNSPECIFIED .
  • [C-4-3] The user MUST be challenged for the primary authentication (egPIN, pattern, password) at least once every 72 hours or less.

If device implementations add or modify the authentication methods to unlock the lock screen based on biometrics, then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-5-1] MUST have a fall-back mechanism to use one of the primary authentication methods which is based on a known secret and meets the requirements to be treated as a secure lock screen.
  • [C-5-2] MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the keguard feature policy by calling the method DevicePolicyManager.setKeyguardDisabledFeatures(KEYGUARD_DISABLE_FINGERPRINT) .
  • [C-5-3] MUST have a false acceptance rate that is equal or stronger than what is required for a fingerprint sensor as described in section 7.3.10, or otherwise MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the password quality policy via the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_BIOMETRIC_WEAK .
  • [C-5-4] The user MUST be challenged for the primary authentication (egPIN, pattern, password) at least once every 72 hours or less.

If device implementations add or modify the authentication methods to unlock the lock screen and if such an authentication method will be used to unlock the keyguard, but will not be treated as a secure lock screen, then they:

9.12.資料刪除

All device implementations:

  • [C-0-1] MUST provide users a mechanism to perform a "Factory Data Reset".
  • [C-0-2] MUST delete all user-generated data. That is, all data except for the following:
    • The system image
    • Any operating system files required by the system image
  • [C-0-3] MUST delete the data in such a way that will satisfy relevant industry standards such as NIST SP800-88.
  • [C-0-4] MUST trigger the above "Factory Data Reset" process when the DevicePolicyManager.wipeData() API is called by the primary user's Device Policy Controller app.
  • MAY provide a fast data wipe option that conducts only a logical data erase.

9.13。 Safe Boot Mode

Android provides Safe Boot Mode, which allows users to boot up into a mode where only preinstalled system apps are allowed to run and all third-party apps are disabled. This mode, known as "Safe Boot Mode", provides the user the capability to uninstall potentially harmful third-party apps.

Device implementations are:

  • [SR] STRONGLY RECOMMENDED to implement Safe Boot Mode.

If device implementations implement Safe Boot Mode, they:

  • [C-1-1] MUST provide the user an option to enter Safe Boot Mode in such a way that is uninterruptible from third-party apps installed on the device, except when the third-party app is a Device Policy Controller and has set the UserManager.DISALLOW_SAFE_BOOT flag as true.

  • [C-1-2] MUST provide the user the capability to uninstall any third-party apps within Safe Mode.

  • SHOULD provide the user an option to enter Safe Boot Mode from the boot menu using a workflow that is different from that of a normal boot.

9.14. Automotive Vehicle System Isolation

Android Automotive devices are expected to exchange data with critical vehicle subsystems by using the vehicle HAL to send and receive messages over vehicle networks such as CAN bus.

The data exchange can be secured by implementing security features below the Android framework layers to prevent malicious or unintentional interaction with these subsystems.

10.軟體相容性測試

Device implementations MUST pass all tests described in this section. However, note that no software test package is fully comprehensive. For this reason, device implementers are STRONGLY RECOMMENDED to make the minimum number of changes as possible to the reference and preferred implementation of Android available from the Android Open Source Project. This will minimize the risk of introducing bugs that create incompatibilities requiring rework and potential device updates.

10.1.相容性測試套件

設備實現:

  • [C-0-1] MUST pass the Android Compatibility Test Suite (CTS) available from the Android Open Source Project, using the final shipping software on the device.

  • [C-0-2] MUST ensure compatibility in cases of ambiguity in CTS and for any reimplementations of parts of the reference source code.

CTS設計為在實際設備上運作。像任何軟體一樣,CTS本身可能包含錯誤。 The CTS will be versioned independently of this Compatibility Definition, and multiple revisions of the CTS may be released for Android 8.0.

設備實現:

  • [C-0-3] MUST pass the latest CTS version available at the time the device software is completed.

  • SHOULD use the reference implementation in the Android Open Source tree as much as possible.

10.2. CTS驗證器

The CTS Verifier is included with the Compatibility Test Suite, and is intended to be run by a human operator to test functionality that cannot be tested by an automated system, such as correct functioning of a camera and sensors.

設備實現:

  • [C-0-1] MUST correctly execute all applicable cases in the CTS verifier.

The CTS Verifier has tests for many kinds of hardware, including some hardware that is optional.

設備實現:

  • [C-0-2] MUST pass all tests for hardware that they possess; for instance, if a device possesses an accelerometer, it MUST correctly execute the Accelerometer test case in the CTS Verifier.

Test cases for features noted as optional by this Compatibility Definition Document MAY be skipped or omitted.

  • [C-0-2] Every device and every build MUST correctly run the CTS Verifier, as noted above. However, since many builds are very similar, device implementers are not expected to explicitly run the CTS Verifier on builds that differ only in trivial ways. Specifically, device implementations that differ from an implementation that has passed the CTS Verifier only by the set of included locales, branding, etc. MAY omit the CTS Verifier test.

11. 可更新的軟體

  • [C-0-1] Device implementations MUST include a mechanism to replace the entirety of the system software. The mechanism need not perform “live” upgrades—that is, a device restart MAY be required.

只要可以替換設備上預先安裝的整個軟體,就可以使用任何方法。例如,以下任何方法都可以滿足此要求:

  • “Over-the-air (OTA)” downloads with offline update via reboot.
  • “Tethered” updates over USB from a host PC.
  • “Offline” updates via a reboot and update from a file on removable storage.

  • [C-0-2] The update mechanism used MUST support updates without wiping user data. That is, the update mechanism MUST preserve application private data and application shared data.請注意,上游Android軟體包括滿足此要求的更新機制。

If the device implementations includes support for an unmetered data connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile, then, they:

  • [C-1-1] MUST support OTA downloads with offline update via reboot.

For device implementations that are launching with Android 6.0 and later, the update mechanism SHOULD support verifying that the system image is binary identical to expected result following an OTA. The block-based OTA implementation in the upstream Android Open Source Project, added since Android 5.1, satisfies this requirement.

Also, device implementations SHOULD support A/B system updates . The AOSP implements this feature using the boot control HAL.

If an error is found in a device implementation after it has been released but within its reasonable product lifetime that is determined in consultation with the Android Compatibility Team to affect the compatibility of third-party applications, then:

  • [C-2-1] The device implementer MUST correct the error via a software update available that can be applied per the mechanism just described.

Android includes features that allow the Device Owner app (if present) to control the installation of system updates. If the system update subsystem for devices report android.software.device_admin then, they:

12. 文件變更日誌

For a summary of changes to the Compatibility Definition in this release:

For a summary of changes to individuals sections:

  1. 介紹
  2. 設備類型
  3. 軟體
  4. Application Packaging
  5. 多媒體
  6. Developer Tools and Options
  7. 硬體相容性
  8. Performance and Power
  9. 安全模型
  10. Software Compatibility Testing
  11. Updatable Software
  12. 文件變更日誌
  13. 聯絡我們

12.1。 Changelog Viewing Tips

Changes are marked as follows:

  • CDD
    Substantive changes to the compatibility requirements.

  • 文件
    Cosmetic or build related changes.

For best viewing, append the pretty=full and no-merges URL parameters to your changelog URLs.

13. 聯絡我們

You can join the android-compatibility forum and ask for clarifications or bring up any issues that you think the document does not cover.