Modifiche al comportamento: tutte le app

La piattaforma Android 16 include modifiche al comportamento che potrebbero influire sulla tua app. Le seguenti modifiche al comportamento si applicano a tutte le app quando vengono eseguite su Android 16, indipendentemente da targetSdkVersion. Dovresti testare l'app e poi modificarla come necessario per supportare queste modifiche, se applicabili.

Assicurati di esaminare anche l'elenco delle modifiche del comportamento che interessano solo le app con target Android 16.

Funzionalità di base

Android 16 (livello API 36) include le seguenti modifiche che modificano o ampliano varie funzionalità di base del sistema Android.

Ottimizzazioni delle quote di JobScheduler

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

Motivo dell'interruzione dei job vuoti abbandonati

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。

Ritiro completo di 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。

L'ambito della priorità di trasmissione ordinata non è più globale

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.

Modifiche interne all'ART

Android 16 include gli aggiornamenti più recenti all'ambiente di runtime Android (ART) che migliorano le prestazioni dell'ambiente di runtime Android (ART) e forniscono il supporto di funzionalità Java aggiuntive. Tramite gli aggiornamenti di sistema di Google Play, questi miglioramenti sono disponibili anche per oltre un miliardo di dispositivi con Android 12 (livello API 31) e versioni successive.

Man mano che queste modifiche vengono rilasciate, le librerie e il codice delle app che si basano sulle strutture interne di ART potrebbero non funzionare correttamente sui dispositivi con Android 16 e sulle versioni precedenti di Android che aggiornano il modulo ART tramite gli aggiornamenti di sistema di Google Play.

Fare affidamento su strutture interne (ad esempio interfacce non SDK) può sempre portare a problemi di compatibilità, ma è particolarmente importante evitare di fare affidamento su codice (o librerie contenenti codice) che sfrutta strutture ART interne, poiché le modifiche ART non sono legate alla versione della piattaforma su cui è in esecuzione il dispositivo e vengono rilasciate su oltre un miliardo di dispositivi tramite gli aggiornamenti di sistema di Google Play.

Tutti gli sviluppatori devono verificare se la loro app è interessata testando le proprie app in modo approfondito su Android 16. Inoltre, controlla i problemi noti per verificare se la tua app dipende da librerie che abbiamo identificato come basate su strutture ART interne. Se hai dipendenze di codice dell'app o della libreria che sono interessate, cerca alternative API pubbliche, se possibile, e richiedi API pubbliche per nuovi casi d'uso creando una richiesta di funzionalità nel nostro issue tracker.

Modalità di compatibilità con le dimensioni pagina di 16 kB

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.

Esperienza utente e interfaccia utente di sistema

Android 16 (livello API 36) include le seguenti modifiche volte a creare un'esperienza utente più coerente e intuitiva.

Ritiro degli annunci di accessibilità che causano interruzioni

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.

Supporto della navigazione con tre pulsanti

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。

Fattori di forma del dispositivo

Android 16 (livello API 36) include le seguenti modifiche per le app quando vengono proiettate sui display dai proprietari di dispositivi virtuali.

Sostituzioni del proprietario del dispositivo virtuale

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

Sicurezza

Android 16 (livello API 36) include modifiche che promuovono la sicurezza del sistema per contribuire a proteggere app e utenti da app dannose.

Maggiore sicurezza contro gli attacchi di reindirizzamento degli intent

Android 16 提供了针对常规 Intent 重定向攻击的默认安全防护，并且所需的兼容性和开发者更改最少。

我们将默认针对 Intent 重定向漏洞引入安全增强解决方案。在大多数情况下，使用 intent 的应用通常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出现故障。

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 内容时，就会出现 Android 中的intent 重定向，而受害应用会在 intent（“顶级”intent）的 extras 字段中启动不可信的子级 intent。这可能会导致攻击者应用在受害应用上下文中启动私有组件、触发特权操作或获得对敏感数据的 URI 访问权限，从而可能导致数据被盗和任意代码执行。

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，这可能很有必要。

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) }

Connettività

Android 16 (livello API 36) include le seguenti modifiche allo stack Bluetooth per migliorare la connettività con i dispositivi periferici.

Gestione migliorata delle perdite di obbligazioni

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。