行为变更:所有应用

Android 16 平台包含一些行为变更,这些变更可能会影响您的应用。以下行为变更将影响在 Android 16 上运行的所有应用,无论采用哪种 targetSdkVersion 都不例外。您应该测试您的应用,然后根据需要进行修改,以支持这些变更(如果适用)。

此外,请务必查看仅影响以 Android 16 为目标平台的应用的行为变更列表。

核心功能

Android 16(API 级别 36)包含以下更改,用于修改或扩展 Android 系统的各种核心功能。

JobScheduler 配额优化

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 while 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 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

被废弃的空作业停止原因

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.

完全弃用 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.

有序广播优先级范围不再是全局

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 内部变更

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 页面大小兼容模式

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。

用户体验和系统界面

Android 16(API 级别 36)进行了以下更改,旨在打造更一致、更直观的用户体验。

废弃干扰性无障碍功能播报

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.

支持“三按钮”导航

Android 16 brings predictive back support to the 3-button navigation for apps that have properly migrated to predictive back. Long-pressing the back button initiates a predictive back animation, giving you a preview of where the back swipe takes you.

This behavior applies across all areas of the system that support predictive back animations, including the system animations (back-to-home, cross-task, and cross-activity).

The predictive back animations in 3-button navigation mode.

设备规格

Android 16(API 级别 36)对虚拟设备所有者将应用投影到显示屏时做出了以下更改。

虚拟设备所有者替换项

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。虚拟设备所有者可以在虚拟设备上运行应用,然后将应用投影到远程设备(例如个人计算机、虚拟现实设备或汽车信息娱乐系统)的显示屏上。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,以将应用投影到远程显示屏。

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在虚拟设备所有者管理的部分虚拟设备上替换应用设置。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部显示屏时忽略屏幕方向、宽高比和可调整大小限制。

常见的破坏性更改

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

参考编号

配套应用串流

安全

Android 16(API 级别 36)进行了一些变更,以提高系统安全性,帮助保护应用和用户免受恶意应用的侵害。

增强了对 intent 重定向攻击的安全防范

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) }

连接

Android 16(API 级别 36)在蓝牙堆栈中进行了以下更改,以改善与外围设备的连接。

改进了对债券损失的处理

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.