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

從 Android 16 開始，我們會根據下列因素調整一般和快速工作執行的執行階段配額：

• 應用程式所屬的應用程式待機值區：在 Android 16 中，系統會開始透過充足的執行階段配額，強制執行有效待機值區。
• 如果工作在應用程式處於頂層狀態時開始執行：在 Android 16 中，如果工作是在應用程式向使用者顯示時啟動，且在應用程式隱藏後繼續執行，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，與前景服務並行執行的工作會遵守工作執行階段配額。如果您使用工作進行使用者啟動的資料移轉，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 安排的工作。如要偵錯工作停止的原因，建議您呼叫 WorkInfo.getStopReason() (如果是 JobScheduler 工作，請呼叫 JobParameters.getStopReason())，記錄工作停止的原因。

如要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」。如要進一步瞭解如何以最佳方式節省電量，請參閱「針對工作排程 API 最佳化電池用量」指南。

此外，我們建議您運用 Android 16 中推出的新版 JobScheduler#getPendingJobReasonsHistory API，瞭解工作未執行的原因。

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功能的覆寫功能。

如要停用「頂端狀態會遵守工作執行階段配額」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階段配額」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

如要測試特定應用程式待命值區行為，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，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

因工作空白而遭捨棄的停止原因

An abandoned job occurs when the JobParameters object associated with the job has been garbage collected, but JobService#jobFinished(JobParameters, boolean) has not been called to signal job completion. This indicates that the job may be running and being rescheduled without the app's awareness.

Apps that rely on JobScheduler, don't maintain a strong reference to the JobParameters object, and timeout will now be granted the new job stop reason STOP_REASON_TIMEOUT_ABANDONED, instead of STOP_REASON_TIMEOUT.

If there are frequent occurrences of the new abandoned stop reason, the system will take mitigation steps to reduce job frequency.

Apps should use the new stop reason to detect and reduce abandoned jobs.

If you're using WorkManager, AsyncTask, or DownloadManager, you aren't impacted because these APIs manage the job lifecycle on your app's behalf.

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 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) 包含下列變更，目的是打造更一致、直觀的使用者體驗。

停止支援干擾性無障礙公告

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 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 在配件裝置配對流程中導入了新行為，以保護使用者的所在位置隱私，避免遭到惡意應用程式竊取。所有在 Android 16 上執行的隨附應用程式，都不再直接透過 RESULT_DISCOVERY_TIMEOUT 收到發現逾時的通知。而是透過視覺對話方塊通知使用者逾時事件。當使用者關閉對話方塊時，應用程式會收到關於 RESULT_USER_REJECTED 關聯失敗的警示。

搜尋時間也從原本的 20 秒延長，使用者可在搜尋期間的任何時間停止裝置探索。如果在開始搜尋的頭 20 秒內發現至少一台裝置，CDM 就會停止搜尋其他裝置。

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.