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,凡是在 Android 16 上執行的應用程式,「一律」都會受到下列行為變更所影響。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

放棄空缺職務的原因

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

JobInfo.Builder#setImportantWhileForeground(boolean) 方法用于在调度应用位于前台或暂时豁免于后台限制时指示作业的优先级。

自 Android 12(API 级别 31)起,此方法已废弃。从 Android 16 开始,它不再有效,系统会忽略调用此方法。

此功能移除也适用于 JobInfo#isImportantWhileForeground()。从 Android 16 开始,如果调用该方法,该方法会返回 false。

已排序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 引入了对 16 KB 内存页面的支持,以优化平台性能。Android 16 添加了兼容模式,让一些针对 4 KB 内存页面构建的应用可以在配置为 16 KB 内存页面的设备上运行。

当您的应用在搭载 Android 16 或更高版本的设备上运行时,如果 Android 检测到您的应用具有 4 KB 对齐的内存页面,则会自动使用兼容模式并向用户显示通知对话框。在 AndroidManifest.xml 中设置 android:pageSizeCompat 属性以启用向后兼容模式,将会阻止应用启动时显示对话框。如需使用 android:pageSizeCompat 属性,请使用 Android 16 SDK 编译您的应用。

为了实现最佳性能、可靠性和稳定性,应用仍应以 16 KB 对齐。如需了解详情,请参阅我们近期发布的博文,了解如何更新应用以支持 16 KB 的内存页面。

兼容模式对话框:当系统检测到 4 KB 对齐的应用在 16 KB 对齐的情况下可以更高效地运行时,系统会显示此对话框。

使用者體驗和系統 UI

Android 16 (API 級別 36) 包含下列變更,旨在打造更一致、直覺的使用者體驗。

淘汰干擾性無障礙公告

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:

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

支援三按鈕操作

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。

自動套用主題色應用程式圖示

从 Android 16 QPR 2 开始,Android 会自动将主题应用于应用图标,以打造一致的主屏幕体验。如果应用未提供自己的带主题的应用图标,就会发生这种情况。应用可以通过在自适应图标中添加单色图层来控制主题化应用图标的设计,并在 Android Studio 中预览应用图标的外观。

裝置板型規格

Android 16 (API 級別 36) 包含下列變更,適用於虛擬裝置擁有者將應用程式投影到螢幕時。

虛擬裝置擁有者覆寫

虚拟设备所有者是创建和管理虚拟设备的可信或特权应用。虚拟设备所有者在虚拟设备上运行应用,然后将应用投影到远程设备的显示屏上,例如个人电脑、虚拟现实设备或车载信息娱乐系统。虚拟设备所有者位于本地设备(例如手机)上。

手机上的虚拟设备所有者创建虚拟设备,将应用投射到远程显示屏。

按应用替换项

在搭载 Android 16(API 级别 36)的设备上,虚拟设备所有者可以替换其管理的特定虚拟设备上的应用设置。例如,为了改进应用布局,虚拟设备所有者可以在将应用投影到外接显示屏时忽略屏幕方向、宽高比和可调整大小限制。

常见破坏性更改

Android 16 行为可能会影响应用在汽车显示屏或 Chromebook 等大屏设备上的界面,尤其是专为纵向小屏幕设计的布局。如需了解如何使应用适应所有设备外形规格,请参阅自适应布局简介。

参考

配套应用串流

安全性

Android 16 (API 級別 36) 包含多項變更,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。

提升安全性,防範意圖重新導向攻擊

Android 16 默认提供针对一般 Intent 重定向攻击的安全防护,只需进行极少的兼容性和开发者更改。

我们正在引入默认安全强化解决方案,以防范 Intent 重定向漏洞。在大多数情况下,正常使用 intent 的应用不会遇到任何兼容性问题;我们在整个开发过程中收集了指标,以监控哪些应用可能会遇到中断。

当攻击者部分或完全控制用于在存在漏洞的应用上下文中启动新组件的 intent 内容,而受害者应用在(“顶级”)intent 的 extra 字段中启动不受信任的子级 intent 时,Android 中就会出现 intent 重定向问题。这可能会导致攻击者应用在受害者应用的上下文中启动私有组件、触发特权操作或获取对敏感数据的 URI 访问权限,从而可能导致数据窃取和任意代码执行。

停用 intent 重定向处理

Android 16 引入了一个新 API,允许应用选择停用启动安全保护。在默认安全行为干扰合法应用用例的特定情况下,可能需要这样做。

对于针对 Android 16(API 级别 36)SDK 或更高版本进行编译的应用

您可以直接对 Intent 对象使用 removeLaunchSecurityProtection() 方法。

val i = intent
val iSublevel: Intent? = i.getParcelableExtra("sub_intent")
iSublevel?.removeLaunchSecurityProtection() // Opt out from hardening
iSublevel?.let { startActivity(it) }
对于针对 Android 15(API 级别 35)或更低版本进行编译的应用

虽然不建议这样做,但您可以使用反射来访问 removeLaunchSecurityProtection() 方法。

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) }

隨附應用程式不會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) 包含下列藍牙堆疊變更,可改善與周邊裝置的連線能力。

改善繫結中斷處理

从 Android 16 开始,蓝牙堆栈已更新,以便在检测到远程配对丢失时提高安全性和用户体验。以前,系统会自动解除配对并启动新的配对流程,这可能会导致意外重新配对。在许多情况下,我们发现应用未以一致的方式处理债券损失事件。

为了统一体验,Android 16 改进了系统的绑定丢失处理。如果之前配对的蓝牙设备在重新连接时无法进行身份验证,系统会断开关联,保留本地配对信息,并显示系统对话框,告知用户配对已断开并指示他们重新配对。