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。您應測試應用程式，並視需要修改，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) 包含下列變更，可修改或擴充 Android 系統的各種核心功能。

JobScheduler 配額最佳化

自 Android 16 起，我們會根據下列因素調整一般和快速工作執行的執行時間配額：

• 應用程式位於哪個應用程式待命值區：在 Android 16 中，系統會開始以充裕的執行階段配額強制執行有效待命值區。
• 如果工作在應用程式處於頂層狀態時開始執行：在 Android 16 中，如果工作在應用程式向使用者顯示時開始執行，並在應用程式不再顯示後繼續執行，則會遵守工作執行時間配額。
• 如果工作在執行前景服務時執行：在 Android 16 中，與前景服務同時執行的工作會遵守工作執行時間配額。如果您要使用工作來進行使用者啟動的資料移轉作業，請考慮改用使用者啟動的資料移轉工作。

這項異動會影響使用 WorkManager、JobScheduler 和 DownloadManager 排定的任務。如要對工作停止的原因進行偵錯，建議您呼叫 WorkInfo.getStopReason() 來記錄工作停止的原因 (JobScheduler 工作請呼叫 JobParameters.getStopReason())。

如要進一步瞭解應用程式狀態如何影響可使用的資源，請參閱「電源管理資源限制」。如要進一步瞭解電池最佳化最佳做法，請參閱最佳化工作排程 API 的電池用量相關指南。

我們也建議您利用 Android 16 中推出的新 JobScheduler#getPendingJobReasonsHistory API，瞭解為何未執行工作。

測試

如要測試應用程式的行為，只要應用程式在 Android 16 裝置上執行，您就可以啟用特定工作配額最佳化設定的覆寫功能。

如要停用「頂層狀態會遵守工作執行時間配額」的強制執行，請執行下列 adb 指令：

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_TOP_STARTED_JOBS APP_PACKAGE_NAME

如要停用「與前景服務同時執行的作業會遵守作業執行時間配額」的強制執行功能，請執行下列 adb 指令：

adb shell am compat enable OVERRIDE_QUOTA_ENFORCEMENT_TO_FGS_JOBS APP_PACKAGE_NAME

如要測試特定的應用程式待命值區行為，您可以使用下列 adb 指令設定應用程式的應用程式待命值區：

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

如要瞭解應用程式所屬的應用程式待命值區，您可以使用下列 adb 指令取得應用程式的應用程式待命值區：

adb shell am get-standby-bucket APP_PACKAGE_NAME

因工作空白而停止的原因

如果与作业关联的 JobParameters 对象已被垃圾回收，但尚未调用 JobService#jobFinished(JobParameters, boolean) 来指示作业已完成，则会发生作业被废弃的情况。这表示作业可能会在应用不知情的情况下运行和重新调度。

依赖于 JobScheduler 的应用不会维护对 JobParameters 对象的强引用，并且超时现在将获得新的作业停止原因 STOP_REASON_TIMEOUT_ABANDONED，而不是 STOP_REASON_TIMEOUT。

如果新的作业被废弃停止原因频繁出现，系统会采取缓解措施来降低作业频率。

应用应使用新的停止原因来检测和减少被废弃的作业。

如果您使用的是 WorkManager、AsyncTask 或 DownloadManager，则不会受到影响，因为这些 API 会代表您的应用管理作业生命周期。

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.

已排序的廣播優先順序範圍不再是全域

Android apps are allowed to define priorities on broadcast receivers to control the order in which the receivers receive and process the broadcast. For manifest-declared receivers, apps can use the android:priority attribute to define the priority and for context-registered receivers, apps can use the IntentFilter#setPriority() API to define the priority. When a broadcast is sent, the system delivers it to receivers in order of their priority, from highest to lowest.

In Android 16, broadcast delivery order using the android:priority attribute or IntentFilter#setPriority() across different processes will not be guaranteed. Broadcast priorities will only be respected within the same application process rather than across all processes.

Also, broadcast priorities will be automatically confined to the range (SYSTEM_LOW_PRIORITY + 1, SYSTEM_HIGH_PRIORITY - 1). Only system components will be allowed to set SYSTEM_LOW_PRIORITY, SYSTEM_HIGH_PRIORITY as broadcast priority.

Your app might be impacted if it does either of the following:

1. Your application has declared multiple processes with the same broadcast intent, and has expectations around receiving those intents in a certain order based on the priority.
2. Your application process interacts with other processes and has expectations around receiving a broadcast intent in a certain order.

If the processes need to coordinate with each other, they should communicate using other coordination channels.

ART 內部變更

Android 16 包含 Android 运行时 (ART) 的最新更新，这些更新可提升 Android 运行时 (ART) 的性能，并支持更多 Java 功能。通过 Google Play 系统更新，搭载 Android 12（API 级别 31）及更高版本的 10 亿多部设备也将受益于这些改进。

发布这些变更后，依赖于 ART 内部结构的库和应用代码在搭载 Android 16 的设备以及通过 Google Play 系统更新来更新 ART 模块的较低 Android 版本上可能无法正常运行。

依赖于内部结构（例如非 SDK 接口）始终会导致兼容性问题，但避免依赖于利用内部 ART 结构的代码（或包含代码的库）尤为重要，因为 ART 更改与设备所运行的平台版本无关，并且会通过 Google Play 系统更新推送到超过 10 亿部设备。

所有开发者都应在 Android 16 上对其应用进行全面测试，以检查其应用是否受到影响。此外，请查看已知问题，了解您的应用是否依赖于我们发现的任何依赖于内部 ART 结构的库。如果您的应用代码或库依赖项受到影响，请尽可能寻找公共 API 替代方案，并在问题跟踪器中创建功能请求，为新用例请求公共 API。

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.

The compatibility mode dialog that displays when the system detects that a 4 KB-aligned app could run more optimally if 16 KB aligned.

使用者體驗和系統 UI

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

淘汰令人混淆的無障礙公告

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.

支援三按鈕操作模式

Android 16 为已正确迁移到预测性返回的应用的三按钮导航栏引入了预测性返回支持。长按返回按钮会启动预测性返回动画，让您预览返回滑动手势会打开的界面。

此行为适用于系统中支持预测性返回动画的所有区域，包括系统动画（返回主屏幕、跨任务和跨 activity）。

“三按钮”导航模式下的预测性返回动画。

支援三按鈕操作模式

Beginning with Android 16 QPR 2, Android automatically applies themes to app icons to create a cohesive home screen experience. This occurs if an app does not provide its own themed app icon. Apps can control the design of their themed app icon by including a monochrome layer within their adaptive icon and previewing what their app icon will look like in Android Studio.

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.

Virtual device owner on phone creates virtual device that projects app to remote display.

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.

Important: Opting out of security protections should be done with caution and only when absolutely necessary, as it can increase the risk of security vulnerabilities. Carefully assess the potential impact on your app's security before using this API.

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.

Caution: Using reflection can make your code more fragile and prone to errors, especially if the underlying API changes in future Android versions. Whenever possible, update your compile SDK to target Android 16 (API level 36) or higher to use the API directly.

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

Starting in Android 16, the Bluetooth stack has been updated to improve security and user experience when a remote bond loss is detected. Previously, the system would automatically remove the bond and initiate a new pairing process, which could lead to unintentional re-pairing. We have seen in many instances apps not taking care of the bond loss event in a consistent way.

To unify the experience, Android 16 improved the bond loss handling to the system. If a previously bonded Bluetooth device could not be authenticated upon reconnection, the system will disconnect the link, retain local bond information, and display a system dialog informing users of the bond loss and directing them to re-pair.