行為變更:指定 Android 16 以上版本的應用程式

和先前版本一樣,Android 16 也包含可能會影響應用程式的行為變更。以下行為變更僅適用於指定 Android 16 以上版本的應用程式。如果您的應用程式指定 Android 16 以上版本,建議您視情況修改應用程式,以支援這些行為。

此外,無論應用程式的 targetSdkVersion 為何,請務必查看影響所有在 Android 16 上執行的應用程式行為變更清單。

使用者體驗和系統使用者介面

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。

無邊框螢幕的選擇不採用功能即將停用

Android 15 enforced edge-to-edge for apps targeting Android 15 (API level 35), but your app could opt-out by setting R.attr#windowOptOutEdgeToEdgeEnforcement to true. For apps targeting Android 16 (API level 36), R.attr#windowOptOutEdgeToEdgeEnforcement is deprecated and disabled, and your app can't opt-out of going edge-to-edge.

  • If your app targets Android 16 (API level 36) and is running on an Android 15 device, R.attr#windowOptOutEdgeToEdgeEnforcement continues to work.
  • If your app targets Android 16 (API level 36) and is running on an Android 16 device, R.attr#windowOptOutEdgeToEdgeEnforcement is disabled.

For testing in Android 16 Beta 3, ensure your app supports edge-to-edge and remove any use of R.attr#windowOptOutEdgeToEdgeEnforcement so that your app also supports edge-to-edge on an Android 15 device. To support edge-to-edge, see the Compose and Views guidance.

必須遷移或選擇不採用預測返回功能

如果應用程式指定 Android 16 (API 級別 36) 以上版本,並在 Android 16 以上版本的裝置上執行,則預設會啟用預測返回系統動畫 (返回首頁、跨工作和跨活動)。此外,系統不會再呼叫 onBackPressed,也不會再調度 KeyEvent.KEYCODE_BACK

如果您的應用程式攔截返回事件,且尚未遷移至預測返回功能,請更新應用程式以使用支援的返回導覽 API。或者,您也可以在應用程式的 AndroidManifest.xml 檔案中,將 <application><activity> 標記中的 android:enableOnBackInvokedCallback 屬性設為 false,暫時停用返回功能。

預測返回主畫面動畫。
預測跨活動動畫。
預測跨工作動畫。

Elegant 字型 API 已淘汰並停用

指定 Android 15 (API 級別 35) 為目標版本的應用程式,其 elegantTextHeight TextView 屬性預設為 true,會將緊湊字型替換為更易閱讀的字型。您可以將 elegantTextHeight 屬性設為 false,即可覆寫這項設定。

Android 16 已淘汰 elegantTextHeight 屬性,且一旦應用程式指定 Android 16 為目標版本,系統就會忽略該屬性。這些 API 控制的「UI 字型」即將停用,因此您應調整所有版面配置,確保阿拉伯文、老撾文、緬甸文、泰米爾文、古吉拉特文、卡納達文、馬拉雅拉姆文、奧底亞文、泰盧固文或泰文的文字算繪作業能保持一致,並能支援日後的版本。

elegantTextHeight 行為 (適用於指定 Android 14 (API 級別 34) 以下版本為目標版本的應用程式,或指定 Android 15 (API 級別 35) 為目標版本的應用程式,且透過將 elegantTextHeight 屬性設為 false 來覆寫預設值)。
elegantTextHeight 行為:針對指定 Android 16 為目標版本的應用程式,或是指定 Android 15 (API 級別 35) 為目標版本的應用程式,但未透過將 elegantTextHeight 屬性設為 false 來覆寫預設值。

核心功能

Android 16 (API 級別 36) 包含下列變更,可修改或擴充 Android 系統的各種核心功能。

固定費率工作排程最佳化

Prior to targeting Android 16, when scheduleAtFixedRate missed a task execution due to being outside a valid process lifecycle, all missed executions immediately execute when the app returns to a valid lifecycle.

When targeting Android 16, at most one missed execution of scheduleAtFixedRate is immediately executed when the app returns to a valid lifecycle. This behavior change is expected to improve app performance. Test this behavior in your app to check if your app is impacted. You can also test by using the app compatibility framework and enabling the STPE_SKIP_MULTIPLE_MISSED_PERIODIC_TASKS compat flag.

裝置板型規格

Android 16 (API 級別 36) 針對在大型螢幕裝置上顯示的應用程式,包含下列變更。

自動調整式版面配置

With Android apps now running on a variety of devices (such as phones, tablets, foldables, desktops, cars, and TVs) and windowing modes on large screens (such as split screen and desktop windowing), developers should build Android apps that adapt to any screen and window size, regardless of device orientation. Paradigms like restricting orientation and resizability are too restrictive in today's multidevice world.

Ignore orientation, resizability, and aspect ratio restrictions

For apps targeting Android 16 (API level 36), Android 16 includes changes to how the system manages orientation, resizability, and aspect ratio restrictions. On displays with smallest width >= 600dp, the restrictions no longer apply. Apps also fill the entire display window, regardless of aspect ratio or a user's preferred orientation, and pillarboxing isn't used.

This change introduces a new standard platform behavior. Android is moving toward a model where apps are expected to adapt to various orientations, display sizes, and aspect ratios. Restrictions like fixed orientation or limited resizability hinder app adaptability, so we recommend making your app adaptive to deliver the best possible user experience.

You can also test this behavior by using the app compatibility framework and enabling the UNIVERSAL_RESIZABLE_BY_DEFAULT compat flag.

Common breaking changes

Ignoring orientation, resizability, and aspect ratio restrictions might impact your app's UI on some devices, especially elements that were designed for small layouts locked in portrait orientation: for example, issues like stretched layouts and off-screen animations and components. Any assumptions about aspect ratio or orientation can cause visual issues with your app. Learn more about how to avoid them and improve your app's adaptive behaviour.

Allowing device rotation results in more activity re-creation, which can result in losing user state if not properly preserved. Learn how to correctly save UI state in Save UI states.

Implementation details

The following manifest attributes and runtime APIs are ignored across large screen devices in full-screen and multi-window modes:

The following values for screenOrientation, setRequestedOrientation(), and getRequestedOrientation() are ignored:

  • portrait
  • reversePortrait
  • sensorPortrait
  • userPortrait
  • landscape
  • reverseLandscape
  • sensorLandscape
  • userLandscape

Regarding display resizability, android:resizeableActivity="false", android:minAspectRatio, and android:maxAspectRatio have no effect.

For apps targeting Android 16 (API level 36), app orientation, resizability, and aspect ratio constraints are ignored on large screens by default, but every app that isn't fully ready can temporarily override this behavior by opting out (which results in the previous behavior of being placed in compatibility mode).

Exceptions

The Android 16 orientation, resizability, and aspect ratio restrictions don't apply in the following situations:

  • Games (based on the android:appCategory flag)
  • Users explicitly opting in to the app's default behavior in aspect ratio settings of the device
  • Screens that are smaller than sw600dp

Opt out temporarily

To opt out a specific activity, declare the PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY manifest property:

<activity ...>
  <property android:name="android.window.PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY" android:value="true" />
  ...
</activity>

If too many parts of your app aren't ready for Android 16, you can opt out completely by applying the same property at the application level:

<application ...>
  <property android:name="android.window.PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY" android:value="true" />
</application>

健康與健身

Android 16 (API 級別 36) 包含下列與健康與健身資料相關的變更。

健康與健身權限

如果應用程式鎖定 Android 16 (API 級別 36) 以上版本,BODY_SENSORS 權限會使用 android.permissions.health 下更精細的權限,而 Health Connect 也會使用這些權限。自 Android 16 起,凡是先前需要 BODY_SENSORSBODY_SENSORS_BACKGROUND 的 API,現在都需要對應的 android.permissions.health 權限。這會影響下列資料類型、API 和前景服務類型:

如果您的應用程式使用這些 API,應要求相應的精細權限:

這些權限與保護從 Health Connect 讀取資料的權限相同,Health Connect 是 Android 的健康、健身和保健資料資料儲存庫。

行動應用程式

行動應用程式如果遷移至使用 READ_HEART_RATE 和其他精細權限,也必須宣告活動,才能顯示應用程式的隱私權政策。這項規定與 Health Connect 相同。

連線能力

Android 16 (API 級別 36) 的藍牙堆疊包含下列變更,可改善與周邊裝置的連線能力。

處理失效連結和加密變更的新意圖

As part of the Improved bond loss handling, Android 16 also introduces 2 new intents to provide apps with greater awareness of bond loss and encryption changes.

Apps targeting Android 16 can now:

  • Receive an ACTION_KEY_MISSING intent when remote bond loss is detected, allowing them to provide more informative user feedback and take appropriate actions.
  • Receive an ACTION_ENCRYPTION_CHANGE intent whenever encryption status of the link changes. This includes encryption status change, encryption algorithm change, and encryption key size change. Apps must consider the bond restored if the link is successfully encrypted upon receiving ACTION_ENCRYPTION_CHANGE intent later.

Adapting to varying OEM implementations

While Android 16 introduces these new intents, their implementation and broadcasting can vary across different device manufacturers (OEMs). To ensure your app provides a consistent and reliable experience across all devices, developers should design their bond loss handling to gracefully adapt to these potential variations.

We recommend the following app behaviors:

  • If the ACTION_KEY_MISSING intent is broadcast:

    The ACL (Asynchronous Connection-Less) link will be disconnected by the system, but the bond information for the device will be retained (as described here).

    Your app should use this intent as the primary signal for bond loss detection and guiding the user to confirm the remote device is in range before initiating device forgetting or re-pairing.

    If a device disconnects after ACTION_KEY_MISSING is received, your app should be cautious about reconnecting, as the device may no longer be bonded with the system.

  • If the ACTION_KEY_MISSING intent is NOT broadcast:

    The ACL link will remain connected, and the bond information for the device will be removed by the system, same to behavior in Android 15.

    In this scenario, your app should continue its existing bond loss handling mechanisms as in previous Android releases, to detect and manage bond loss events.

移除藍牙連結的新方法

所有以 Android 16 為目標版本的應用程式,現在都能使用 CompanionDeviceManager 中的公開 API 解除配對藍牙裝置。如果隨附裝置是以 CDM 關聯方式管理,應用程式可以在關聯裝置上使用新的 removeBond(int) API 觸發藍牙連結移除作業。應用程式可以監控連結狀態變更,方法是監聽藍牙裝置廣播事件 ACTION_BOND_STATE_CHANGED

安全性

Android 16 (API 級別 36) 包含下列安全性變更。

MediaStore 版本鎖定

For apps targeting Android 16 or higher, MediaStore#getVersion() will now be unique to each app. This eliminates identifying properties from the version string to prevent abuse and usage for fingerprinting techniques. Apps shouldn't make any assumptions around the format of this version. Apps should already handle version changes when using this API and in most cases shouldn't need to change their current behavior, unless the developer has attempted to infer additional information that is beyond the intended scope of this API.

更安全的意圖

The Safer Intents feature is a multi-phase security initiative designed to improve the security of Android's intent resolution mechanism. The goal is to protect apps from malicious actions by adding checks during intent processing and filtering intents that don't meet specific criteria.

In Android 15 the feature focused on the sending app, now with Android 16, shifts control to the receiving app, allowing developers to opt-in to strict intent resolution using their app manifest.

Two key changes are being implemented:

  1. Explicit Intents Must Match the Target Component's Intent Filter: If an intent explicitly targets a component, it should match that component's intent filter.

  2. Intents Without an Action Cannot Match any Intent Filter: Intents that don't have an action specified shouldn't be resolved to any intent filter.

These changes only apply when multiple apps are involved and don't affect intent handling within a single app.

Impact

The opt-in nature means that developers must explicitly enable it in their app manifest for it to take effect. As a result, the feature's impact will be limited to apps whose developers:

  • Are aware of the Safer Intents feature and its benefits.
  • Actively choose to incorporate stricter intent handling practices into their apps.

This opt-in approach minimizes the risk of breaking existing apps that may rely on the current less-secure intent resolution behavior.

While the initial impact in Android 16 may be limited, the Safer Intents initiative has a roadmap for broader impact in future Android releases. The plan is to eventually make strict intent resolution the default behavior.

The Safer Intents feature has the potential to significantly enhance the security of the Android ecosystem by making it more difficult for malicious apps to exploit vulnerabilities in the intent resolution mechanism.

However, the transition to opt-out and mandatory enforcement must be carefully managed to address potential compatibility issues with existing apps.

Implementation

Developers need to explicitly enable stricter intent matching using the intentMatchingFlags attribute in their app manifest. Here is an example where the feature is opt-in for the entire app, but disabled/opt-out on a receiver:

<application android:intentMatchingFlags="enforceIntentFilter">
    <receiver android:name=".MyBroadcastReceiver" android:exported="true" android:intentMatchingFlags="none">
        <intent-filter>
            <action android:name="com.example.MY_CUSTOM_ACTION" />
        </intent-filter>
        <intent-filter>
            <action android:name="com.example.MY_ANOTHER_CUSTOM_ACTION" />
        </intent-filter>
    </receiver>
</application>

More on the supported flags:

Flag Name Description
enforceIntentFilter Enforces stricter matching for incoming intents
none Disables all special matching rules for incoming intents. When specifying multiple flags, conflicting values are resolved by giving precedence to the "none" flag
allowNullAction Relaxes the matching rules to allow intents without an action to match. This flag to be used in conjunction with "enforceIntentFilter" to achieve a specific behavior

Testing and Debugging

When the enforcement is active, apps should function correctly if the intent caller has properly populated the intent. However, blocked intents will trigger warning log messages like "Intent does not match component's intent filter:" and "Access blocked:" with the tag "PackageManager." This indicates a potential issue that could impact the app and requires attention.

Logcat filter:

tag=:PackageManager & (message:"Intent does not match component's intent filter:" | message: "Access blocked:")

隱私權

Android 16 (API 級別 36) 包含下列隱私權變更。

區域網路權限

任何具備 INTERNET 權限的應用程式,都可以存取區域網路上的裝置。這麼做可讓應用程式輕鬆連線至本機裝置,但也會影響隱私權,例如形成使用者的指紋,以及成為位置資訊的代理程式。

區域網路保護專案旨在透過新的執行階段權限,限制使用者存取區域網路的權限,以保護使用者的隱私權。

發布計畫

這項異動將分別在 25Q2 和 TBD 兩個版本之間部署。開發人員必須遵循這項 25Q2 指南並提供意見回饋,因為這些防護措施將在後續 Android 版本中強制執行。此外,他們還需要根據下列指南更新依賴隱含本機網路存取權的情況,並為使用者拒絕和撤銷新權限做好準備。

影響

在目前階段,LNP 是選擇加入功能,也就是說只有選擇加入的應用程式會受到影響。選擇加入階段的目標,是讓應用程式開發人員瞭解應用程式的哪些部分依賴隱含的本機網路存取權,以便在下次發布時做好權限保護的準備。

如果應用程式使用以下方式存取使用者的本機網路,就會受到影響:

  • 在本機網路位址上直接或透過程式庫使用原始網路介面 (例如 mDNS 或 SSDP 服務探索通訊協定)
  • 使用可存取本機網路的架構層級類別 (例如 NsdManager)

區域網路位址的流量,需要區域網路存取權。下表列出一些常見的情況:

應用程式低層級網路作業 需要區域網路權限
建立傳出 TCP 連線
接受傳入的 TCP 連線
傳送 UDP 單播、多播、廣播
接收傳入的 UDP 單播、多點傳播、廣播

這些限制是在網路堆疊中深層實作,因此適用於所有網路 API。這包括在原生或受管理程式碼中建立的通訊端,Cronet 和 OkHttp 等網路程式庫,以及在這些項目上實作的任何 API。嘗試解析區域網路上的服務 (也就是具有 .local 後置字元的服務) 時,必須具備區域網路權限。

上述規則的例外狀況:

  • 如果裝置的 DNS 伺服器位於區域網路中,則進出該伺服器的流量 (在通訊埠 53) 不需要區域網路存取權。
  • 使用 Output Switcher 做為應用程式內挑選器的應用程式不需要區域網路權限 (2025Q4 將提供更多指引)。

開發人員指南 (選擇採用)

如要啟用區域網路限制,請按照下列步驟操作:

  1. 將裝置刷新至搭載 25Q2 Beta 3 以上版本的版本。
  2. 安裝要測試的應用程式。
  3. 在 ADB 中切換 Appcompat 標記:

    adb shell am compat enable RESTRICT_LOCAL_NETWORK <package_name>
    
  4. 重新啟動裝置

應用程式現在無法存取區域網路,任何嘗試存取區域網路的動作都會導致通訊端錯誤。如果您使用的是可在應用程式程序外執行本機網路作業的 API (例如 NsdManager),這些 API 在選擇加入階段不會受到影響。

如要恢復存取權,您必須授予應用程式 NEARBY_WIFI_DEVICES 權限。

  1. 請確認應用程式在資訊清單中宣告 NEARBY_WIFI_DEVICES 權限。
  2. 依序前往「設定」>「應用程式」>「[應用程式名稱]」>「權限」>「鄰近裝置」>「允許」

應用程式現在應已恢復對本機網路的存取權,所有情境應可如同選擇加入應用程式前一樣運作。

當區域網路保護措施開始生效後,應用程式網路流量會受到以下影響。

權限 傳出 LAN 要求 傳出/傳入網際網路要求 傳入 LAN 要求
已授權 Works Works Works
未授予 凸槌影片 Works 凸槌影片

使用下列指令切換關閉 App-Compat 標記

adb shell am compat disable RESTRICT_LOCAL_NETWORK <package_name>

錯誤

只要呼叫端的通訊端點對本機網路位址呼叫 send 或 send 變數,就會傳回因這些限制而發生的錯誤。

錯誤示例:

sendto failed: EPERM (Operation not permitted)

sendto failed: ECONNABORTED (Operation not permitted)

區域網路定義

本專案中的本機網路是指使用可廣播網路介面的 IP 網路,例如 Wi-Fi 或乙太網路,但不包含行動網路 (WWAN) 或 VPN 連線。

以下是本機網路:

IPv4:

  • 169.254.0.0/16 // 連結本機
  • 100.64.0.0/10 // CGNAT
  • 10.0.0.0/8 // RFC1918
  • 172.16.0.0/12 // RFC1918
  • 192.168.0.0/16 // RFC1918

IPv6:

  • 連結本機
  • 直接連線路徑
  • 類似 Thread 的網路半成品
  • 多個子網路 (待定)

此外,多播位址 (224.0.0.0/4、ff00::/8) 和 IPv4 廣播位址 (255.255.255.255) 都歸類為本機網路位址。

應用程式擁有的相片

當指定 SDK 36 以上版本的應用程式在搭載 Android 16 以上版本的裝置上執行時,如果系統提示使用者授予相片和影片權限,選擇限制所選媒體存取權的使用者會在相片挑選器中看到應用程式預先選取的所有相片。使用者可以取消選取任何預先選取的項目,這樣一來,應用程式就無法存取這些相片和影片。