行為變更：所有應用程式

Android 16 平台包含可能對應用程式造成影響的行為變更。無論 targetSdkVersion 為何，當應用程式在 Android 16 上執行時，下列行為變更將會套用至所有應用程式。您必須測試自己的應用程式，並視需要進行修改，以便在適當情況下支援這些變更。

另請務必查看僅對指定 Android 16 為目標版本的應用程式造成影響的行為變更。

核心功能

Android 16 (API 級別 36) 包含下列異動項目，這類變更會修改或擴充 Android 系統的各種核心功能。

JobScheduler 配額最佳化

Starting in Android 16, we're adjusting regular and expedited job execution runtime quota based on the following factors:

• Which app standby bucket the application is in: in Android 16, active standby buckets will start being enforced by a generous runtime quota.
• If the job starts execution while the app is in a top state: in Android 16, Jobs started while the app is visible to the user and continues after the app becomes invisible, will adhere to the job runtime quota.
• If the job is executing while running a Foreground Service: in Android 16, jobs that are executing concurrently with a foreground service will adhere to the job runtime quota. If you're leveraging jobs for user initiated data transfer, consider using user initiated data transfer jobs instead.

This change impacts tasks scheduled using WorkManager, JobScheduler, and DownloadManager. To debug why a job was stopped, we recommend logging why your job was stopped by calling WorkInfo.getStopReason() (for JobScheduler jobs, call JobParameters.getStopReason()).

For information about how your app's state affects the resources it can use, see Power management resource limits. For more information on battery-optimal best practices, refer to guidance on optimize battery use for task scheduling APIs.

We also recommend leveraging the new JobScheduler#getPendingJobReasonsHistory API introduced in Android 16 to understand why a job has not executed.

Testing

To test your app's behavior, you can enable override of certain job quota optimizations as long as the app is running on an Android 16 device.

To disable enforcement of "top state will adhere to job runtime quota", run the following adb command:

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_TOP_STARTED_JOBS APP_PACKAGE_NAME

To disable enforcement of "jobs that are executing while concurrently with a foreground service will adhere to the job runtime quota", run the following adb command:

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_FGS_JOBS APP_PACKAGE_NAME

To test certain app standby bucket behavior, you can set the app standby bucket of your app using the following adb command:

adb shell am set-standby-bucket APP_PACKAGE_NAME active|working_set|frequent|rare|restricted

To understand the app standby bucket your app is in, you can get the app standby bucket of your app using the following adb command:

adb shell am get-standby-bucket APP_PACKAGE_NAME

放棄空白工作停止原因

當與工作相關聯的 JobParameters 物件已收集為垃圾，但未呼叫 JobService#jobFinished(JobParameters, boolean) 來傳送工作完成信號時，就會發生遺棄的工作。這表示工作可能在未經應用程式察覺的情況下執行及重新排程。

依賴 JobScheduler 的應用程式不會維持對 JobParameters 物件的強參照，且超時現在會授予新的 STOP_REASON_TIMEOUT_ABANDONED 工作停止原因，而非 STOP_REASON_TIMEOUT。

如果新棄站原因經常發生，系統會採取緩解措施來減少工作頻率。

應用程式應使用新的停止原因來偵測並減少遺失的工作。

如果您使用 WorkManager、AsyncTask 或 DownloadManager，則不會受到影響，因為這些 API 會代表應用程式管理工作生命週期。

完全淘汰 JobInfo#setImportantWhileForeground

The JobInfo.Builder#setImportantWhileForeground(boolean) method indicates the importance of a job while the scheduling app is in the foreground or when temporarily exempted from background restrictions.

This method has been deprecated since Android 12 (API level 31). Starting in Android 16, it no longer functions effectively and calling this method will be ignored.

This removal of functionality also applies to JobInfo#isImportantWhileForeground(). Starting in Android 16, if the method is called, the method returns false.

已排序的播送優先順序範圍不再是全域

Android 應用程式可定義廣播接收器的優先順序，藉此控制接收器接收及處理廣播的順序。對於資訊清單宣告的接收器，應用程式可以使用 android:priority 屬性來定義優先順序，而對於內容註冊的接收器，應用程式可以使用 IntentFilter#setPriority() API 來定義優先順序。傳送廣播訊息時，系統會依優先順序 (由高至低) 將訊息傳送給接收器。

在 Android 16 中，系統無法保證使用 android:priority 屬性或在不同程序中使用 IntentFilter#setPriority() 的廣播傳送順序。廣播優先順序只會在相同的應用程式程序中受到尊重，而不會跨所有程序。

此外，廣播優先順序會自動限制在 (SYSTEM_LOW_PRIORITY + 1, SYSTEM_HIGH_PRIORITY - 1) 的範圍內。只有系統元件可將 SYSTEM_LOW_PRIORITY、SYSTEM_HIGH_PRIORITY 設為廣播優先順序。

如果您的應用程式執行下列任一操作，可能會受到影響：

1. 您的應用程式已宣告多個使用相同廣播意圖的程序，並且預期會按照優先順序接收這些意圖。
2. 您的應用程式程序會與其他程序互動，並預期以特定順序接收廣播意圖。

如果程序需要相互協調，則應使用其他協調管道進行通訊。

ART 內部變更

Android 16 includes the latest updates to the Android Runtime (ART) that improve the Android Runtime's (ART's) performance and provide support for additional Java features. Through Google Play System updates, these improvements are also available to over a billion devices running Android 12 (API level 31) and higher.

As these changes are released, libraries and app code that rely on internal structures of ART might not work correctly on devices running Android 16, along with earlier Android versions that update the ART module through Google Play system updates.

Relying on internal structures (such as non-SDK interfaces) can always lead to compatibility problems, but it's particularly important to avoid relying on code (or libraries containing code) that leverages internal ART structures, since ART changes aren't tied to the platform version the device is running on and they go out to over a billion devices through Google Play system updates.

All developers should check whether their app is impacted by testing their apps thoroughly on Android 16. In addition, check the known issues to see if your app depends on any libraries that we've identified that rely on internal ART structures. If you do have app code or library dependencies that are affected, seek public API alternatives whenever possible and request public APIs for new use cases by creating a feature request in our issue tracker.

16 KB 頁面大小相容模式

Android 15 introduced support for 16 KB memory pages to optimize performance of the platform. Android 16 adds a compatibility mode, allowing some apps built for 4 KB memory pages to run on a device configured for 16 KB memory pages.

When your app is running on a device with Android 16 or higher, if Android detects that your app has 4 KB aligned memory pages, it automatically uses compatibility mode and display a notification dialog to the user. Setting the android:pageSizeCompat property in the AndroidManifest.xml to enable the backwards compatibility mode will prevent the display of the dialog when your app launches. To use the android:pageSizeCompat property, compile your app using the Android 16 SDK.

For best performance, reliability, and stability, your app should still be 16 KB aligned. Check out our recent blog post on updating your apps to support 16 KB memory pages for more details.

使用者體驗和系統 UI

Android 16 (API 級別 36) 包含下列異動，目的是打造更一致、直觀的使用者體驗。

停用令人混淆的無障礙工具公告

Android 16 deprecates accessibility announcements, characterized by the use of announceForAccessibility or the dispatch of TYPE_ANNOUNCEMENT accessibility events. These can create inconsistent user experiences for users of TalkBack and Android's screen reader, and alternatives better serve a broader range of user needs across a variety of Android's assistive technologies.

Examples of alternatives:

• For significant UI changes like window changes, use Activity.setTitle(CharSequence) and setAccessibilityPaneTitle(java.lang.CharSequence). In Compose, use Modifier.semantics { paneTitle = "paneTitle" }
• To inform the user of changes to critical UI, use setAccessibilityLiveRegion(int). In Compose, use Modifier.semantics { liveRegion = LiveRegionMode.[Polite|Assertive]} . These should be used sparingly as they may generate announcements every time a View is updated.
• To notify users about errors, send an AccessibilityEvent of type AccessibilityEvent#CONTENT_CHANGE_TYPE_ERROR and set AccessibilityNodeInfo#setError(CharSequence), or use TextView#setError(CharSequence).

The reference documentation for the deprecated announceForAccessibility API includes more details about suggested alternatives.

支援三按鈕操作

Android 16 為已正確遷移至預測返回功能的應用程式，提供 3 鍵導覽的預測返回功能支援。長按返回按鈕會啟動預測返回動畫，讓您預覽返回滑動手勢會帶您前往的位置。

這項行為適用於系統中所有支援預測返回動畫的區域，包括系統動畫 (返回首頁、跨工作和跨活動)。

自動套用主題色應用程式圖示

從 Android 16 QPR 2 開始，Android 會自動將主題套用至應用程式圖示，打造一致的主畫面體驗。如果應用程式未提供自己的主題式應用程式圖示，就會發生這種情況。應用程式可以在自動調整式圖示中加入單色圖層，並在 Android Studio 中預覽應用程式圖示的外觀，藉此控制主題式應用程式圖示的設計。

裝置板型規格

Android 16 (API 級別 36) 包含以下變更，適用於虛擬裝置擁有者將應用程式投放到螢幕時。

虛擬裝置擁有者覆寫

A virtual device owner is a trusted or privileged app that creates and manages a virtual device. Virtual device owners run apps on a virtual device and then project the apps to the display of a remote device, such as a personal computer, virtual reality device, or car infotainment system. The virtual device owner is on a local device, such as a mobile phone.

Per-app overrides

On devices running Android 16 (API level 36), virtual device owners can override app settings on select virtual devices that the virtual device owners manage. For example, to improve app layout, a virtual device owner can ignore orientation, aspect ratio, and resizability restrictions when projecting apps onto an external display.

Common breaking changes

The Android 16 behavior might impact your app's UI on large screen form factors such as car displays or Chromebooks, especially layouts that were designed for small displays in portrait orientation. To learn how to make your app adaptive for all device form factors, see About adaptive layouts.

References

Companion app streaming

安全性

Android 16 (API 級別 36) 包含多項異動，可提升系統安全性，協助保護應用程式和使用者免受惡意應用程式侵害。

安全性提高，避免意圖重新導向攻擊

Android 16 provides default security against general Intent redirection attacks, with minimum compatibility and developer changes required.

We are introducing by-default security hardening solutions to Intent redirection exploits. In most cases, apps that use intents normally won't experience any compatibility issues; we've gathered metrics throughout our development process to monitor which apps might experience breakages.

Intent redirection in Android occurs when an attacker can partly or fully control the contents of an intent used to launch a new component in the context of a vulnerable app, while the victim app launches an untrusted sub-level intent in an extras field of an ("top-level") Intent. This can lead to the attacker app launching private components in the context of the victim app, triggering privileged actions, or gaining URI access to sensitive data, potentially leading to data theft and arbitrary code execution.

Opt out of Intent redirection handling

Android 16 introduces a new API that allows apps to opt out of launch security protections. This might be necessary in specific cases where the default security behavior interferes with legitimate app use cases.

For applications compiling against Android 16 (API level 36) SDK or higher

You can directly use the removeLaunchSecurityProtection() method on the Intent object.

val i = intent
val iSublevel: Intent? = i.getParcelableExtra("sub_intent")
iSublevel?.removeLaunchSecurityProtection() // Opt out from hardening
iSublevel?.let { startActivity(it) }

For applications compiling against Android 15 (API level 35) or lower

While not recommended, you can use reflection to access the removeLaunchSecurityProtection() method.

val i = intent
val iSublevel: Intent? = i.getParcelableExtra("sub_intent", Intent::class.java)
try {
    val removeLaunchSecurityProtection = Intent::class.java.getDeclaredMethod("removeLaunchSecurityProtection")
    removeLaunchSecurityProtection.invoke(iSublevel)
} catch (e: Exception) {
    // Handle the exception, e.g., log it
} // Opt-out from the security hardening using reflection
iSublevel?.let { startActivity(it) }

隨附應用程式不再收到探索逾時通知

Android 16 introduces a new behavior during companion device pairing flow to protect the user's location privacy from malicious apps. All companion apps running on Android 16 are no longer directly notified of discovery timeout using RESULT_DISCOVERY_TIMEOUT. Instead, the user is notified of timeout events with a visual dialog. When the user dismisses the dialog, the app is alerted of the association failure with RESULT_USER_REJECTED.

The search duration has also been extended from the original 20 seconds, and the device discovery can be stopped by the user at any point during the search. If at least one device was discovered within the first 20 seconds of starting the search, the CDM stops searching for additional devices.

連線能力

Android 16 (API 級別 36) 的藍牙堆疊包含下列變更，可提升與周邊裝置的連線能力。

改善債券損失處理方式

自 Android 16 起，我們已更新藍牙堆疊，以便在偵測到遠端連結遺失時，提升安全性和使用者體驗。先前系統會自動移除配對連結，並啟動新的配對程序，這可能會導致不小心重新配對。我們發現許多應用程式並未以一致的方式處理連結失效事件。

為統一使用體驗，Android 16 改善了系統的連結遺失處理方式。如果先前已配對的藍牙裝置無法在重新連線時驗證，系統會中斷連結、保留本機配對資訊，並顯示系統對話方塊，告知使用者配對失敗，並引導他們重新配對。