Modifiche al comportamento: tutte le app

La piattaforma Android 14 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 14, indipendentemente da targetSdkVersion. Dovresti testare la tua app e poi modificarla in base alle necessità per supportarle correttamente, ove applicabile.

Assicurati di esaminare anche l'elenco delle modifiche al comportamento che interessano solo le app con target Android 14.

Funzionalità di base

Le sveglie esatte programmate sono vietate per impostazione predefinita

Exact alarms are meant for user-intentioned notifications, or for actions that need to happen at a precise time. Starting in Android 14, the SCHEDULE_EXACT_ALARM permission is no longer being pre-granted to most newly installed apps targeting Android 13 and higher—the permission is denied by default.

Learn more about the changes to the permission for scheduling exact alarms.

Le trasmissioni registrate in base al contesto vengono messe in coda mentre le app vengono memorizzate nella cache

在 Android 14 中，当应用处于缓存状态时，系统可以将上下文注册的广播放入队列中。这与 Android 12（API 级别 31）为异步 binder 事务引入的队列行为类似。在清单中声明的广播不会加入队列，并且应用会从缓存状态中移除以进行广播传递。

当应用离开缓存状态（例如返回前台）时，系统会传递所有已加入队列的广播。某些广播的多个实例 可能会合并为一个广播。取决于其他因素，如系统 运行状况，则可能会从缓存状态中移除应用，以及之前排队 广播。

Le app possono terminare solo le proprie procedure in background

Starting in Android 14, when your app calls killBackgroundProcesses(), the API can kill only the background processes of your own app.

If you pass in the package name of another app, this method has no effect on that app's background processes, and the following message appears in Logcat:

Invalid packageName: com.example.anotherapp

Your app shouldn't use the killBackgroundProcesses() API or otherwise attempt to influence the process lifecycle of other apps, even on older OS versions. Android is designed to keep cached apps in the background and kill them automatically when the system needs memory. If your app kills other apps unnecessarily, it can reduce system performance and increase battery consumption by requiring full restarts of those apps later, which takes significantly more resources than resuming an existing cached app.

Note: It isn't possible for a 3rd-party application to improve the memory, power, or thermal behavior of an Android device. You should ensure that your app is compliant with Google Play's policy regarding misleading claims.

L'MTU è impostato su 517 per il primo client GATT che richiede un MTU

从 Android 14 开始，Android 蓝牙堆栈会更严格地遵循 蓝牙核心规范 5.2 版，并在第一个 GATT 客户端使用 BluetoothGatt#requestMtu(int) API 请求 MTU 时将 BLE ATT MTU 请求设为 517 字节，并忽略该 ACL 连接上的所有后续 MTU 请求。

注意 ：除非外围设备未正确处理 MTU 协商并接受任何 MTU 大小（即使不支持），否则此更改不会产生影响。在这种情况下，当您的应用从 Android 14 设备发送大量数据时，可能会导致出现问题。

如需解决此更改并使您的应用更为稳健，请考虑以下选项：

• 您的外围设备应使用外围设备可以容纳的合理值来响应 Android 设备的 MTU 请求。最终协商的值将是 Android 请求的值和远程提供的值（例如 min(517, remoteMtu)）的较小值
  • 实现此修复程序可能需要更新外围设备的固件
• 或者，您也可以根据外围设备的已知支持值与收到的 MTU 更改值之间的最小值来限制 GATT 特征写入
  • 提醒您，应将标头的支持大小减小 5 个字节
  • 例如：arrayMaxLength = min(SUPPORTED_MTU, GATT_MAX_ATTR_LEN(517)) - 5

Nuovo motivo per cui un'app può essere inserita nel bucket in standby con limitazioni

Android 14 introduces a new reason an app can be placed into the restricted standby bucket. The app's jobs trigger ANR errors multiple times due to onStartJob, onStopJob, or onBind method timeouts. (See JobScheduler reinforces callback and network behavior for changes to onStartJob and onStopJob.)

Note: See power management to see how the app is impacted if it is placed into the restricted bucket. The app is moved back to the active bucket when the user launches the app to the foreground, just as in previous Android versions.

To track whether or not the app has entered the restricted standby bucket, we recommend logging with the API UsageStatsManager.getAppStandbyBucket() on job execution or UsageStatsManager.queryEventsForSelf() on app startup.

mlock limitato a 64 KB

在 Android 14（API 级别 34）及更高版本中，平台将可使用 mlock() 锁定的最大内存量减少到每个进程 64 KB。在之前的版本中，每个进程的上限为 64 MB。此限制有助于更好地管理应用和系统的内存。为了在各种设备上提供更一致的体验，Android 14 针对兼容设备上的新 mlock() 限制添加了一项新的 CTS 测试。

Il sistema applica l'utilizzo delle risorse delle app memorizzate nella cache

By design, an app's process is in a cached state when it's moved to the background and no other app process components are running. Such an app process is subject to being killed due to system memory pressure. Any work that Activity instances perform after the onStop() method has been called and returned, while in this state, is unreliable and strongly discouraged.

Android 14 introduces consistency and enforcement to this design. Shortly after an app process enters a cached state, background work is disallowed, until a process component re-enters an active state of the lifecycle.

Apps that use typical framework-supported lifecycle APIs – such as services, JobScheduler, and Jetpack WorkManager – shouldn't be impacted by these changes.

Esperienza utente

Modifiche all'esperienza degli utenti con le notifiche non ignorabili

If your app shows non-dismissable foreground notifications to users, Android 14 has changed the behavior to allow users to dismiss such notifications.

This change applies to apps that prevent users from dismissing foreground notifications by setting Notification.FLAG_ONGOING_EVENT through Notification.Builder#setOngoing(true) or NotificationCompat.Builder#setOngoing(true). The behavior of FLAG_ONGOING_EVENT has changed to make such notifications actually dismissable by the user.

These kinds of notifications are still non-dismissable in the following conditions:

• When the phone is locked
• If the user selects a Clear all notification action (which helps with accidental dismissals)

Also, this new behavior doesn't apply to notifications in the following use cases:

• CallStyle notifications
• Device policy controller (DPC) and supporting packages for enterprise
• Media notifications
• The default Search Selector package

Le informazioni sulla sicurezza dei dati sono più visibili

Per migliorare la privacy degli utenti, Android 14 aumenta il numero di punti in cui il sistema mostra le informazioni che hai dichiarato nel modulo di Play Console. Al momento, gli utenti possono visualizzare queste informazioni nella sezione Sicurezza dei dati della scheda della tua app su Google Play.

Ti invitiamo a esaminare le norme relative alla condivisione dei dati sulla posizione della tua app e a apportare eventuali aggiornamenti alla sezione Sicurezza dei dati di Google Play della tua app.

Scopri di più nella guida su come le informazioni sulla sicurezza dei dati sono più visibili su Android 14.

Accessibilità

Ridimensionamento non lineare dei caratteri al 200%

A partire da Android 14, il sistema supporta la scalabilità dei caratteri fino al 200%, offrendo agli utenti ipovedenti opzioni di accessibilità aggiuntive in linea con le linee guida per l'accessibilità dei contenuti web (WCAG).

Se utilizzi già unità di pixel scalabili (sp) per definire le dimensioni del testo, questa variazione probabilmente non avrà un impatto elevato sulla tua app. Tuttavia, devi eseguire test dell'interfaccia utente con le dimensioni dei caratteri massime attivate (200%) per verificare che la tua app possa supportare dimensioni dei caratteri più grandi senza influire sulla usabilità.

Sicurezza

Livello API target installabile minimo

Starting with Android 14, apps with a targetSdkVersion lower than 23 can't be installed. Requiring apps to meet these minimum target API level requirements improves security and privacy for users.

Malware often targets older API levels in order to bypass security and privacy protections that have been introduced in newer Android versions. For example, some malware apps use a targetSdkVersion of 22 to avoid being subjected to the runtime permission model introduced in 2015 by Android 6.0 Marshmallow (API level 23). This Android 14 change makes it harder for malware to avoid security and privacy improvements. Attempting to install an app targeting a lower API level will result in an installation failure, with the following message appearing in Logcat:

INSTALL_FAILED_DEPRECATED_SDK_VERSION: App package must target at least SDK version 23, but found 7

On devices upgrading to Android 14, any apps with a targetSdkVersion lower than 23 will remain installed.

If you need to test an app targeting an older API level, use the following ADB command:

adb install --bypass-low-target-sdk-block FILENAME.apk

I nomi dei pacchetti dei proprietari dei media potrebbero essere oscurati

The media store supports queries for the OWNER_PACKAGE_NAME column, which indicates the app that stored a particular media file. Starting in Android 14, this value is redacted unless at least one of the following conditions is true:

• The app that stored the media file has a package name that is always visible to other apps.

• The app that queries the media store requests the QUERY_ALL_PACKAGES permission.

  Caution: Use of the QUERY_ALL_PACKAGES permission is subject to Google Play Policy.

Learn more about how Android filters package visibility for privacy purposes.