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 UI

Android 16 (API 級別 36) 包含下列異動，旨在打造更一致、直觀的使用者體驗。

無邊框設計停用選項即將移除

Android 15 對以 Android 15 (API 級別 35) 為目標版本的應用程式強制執行無邊框設計，但您可以將 R.attr#windowOptOutEdgeToEdgeEnforcement 設為 true，選擇不採用這項設計。如果應用程式指定 Android 16 (API 級別 36) 為目標，系統會淘汰並停用 R.attr#windowOptOutEdgeToEdgeEnforcement，且應用程式無法選擇不採用無邊框設計。

• 如果應用程式指定 Android 16 (API 級別 36) 版本為目標，且在 Android 15 裝置上執行，R.attr#windowOptOutEdgeToEdgeEnforcement 仍可正常運作。
• 如果應用程式指定 Android 16 (API 級別 36)，且在 Android 16 裝置上執行，系統會停用 R.attr#windowOptOutEdgeToEdgeEnforcement。

如要在 Android 16 中進行測試，請確保應用程式支援無邊框設計，並移除所有 R.attr#windowOptOutEdgeToEdgeEnforcement 的使用情形，讓應用程式也能在 Android 15 裝置上支援無邊框設計。如要支援無邊框設計，請參閱 Compose 和 Views 指南。

必須遷移或停用預測返回手勢

如果應用程式指定 Android 16 (API 級別 36) 以上版本，且在搭載 Android 16 以上版本的裝置上執行，系統會預設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，也不會再傳送 KeyEvent.KEYCODE_BACK。

如果應用程式會攔截返回事件，但您尚未遷移至預測返回手勢，請更新應用程式以使用支援的返回導覽 API，或暫時停用預測返回手勢，方法是在應用程式 AndroidManifest.xml 檔案的 <application> 或 <activity> 標記中，將 android:enableOnBackInvokedCallback 屬性設為 false。

優雅字型 API 已淘汰並停用

指定 Android 15 (API 級別 35) 的應用程式會預設將 elegantTextHeight TextView 屬性設為 true，以更易於閱讀的字型取代精簡字型。您可以將 elegantTextHeight 屬性設為 false，藉此覆寫這項設定。

Android 16 會淘汰 elegantTextHeight 屬性，應用程式指定 Android 16 後，系統就會忽略該屬性。這些 API 控制的「UI 字型」即將停用，因此請調整所有版面配置，確保阿拉伯文、寮文、緬甸文、泰米爾文、古吉拉特文、卡納達文、馬拉雅拉姆文、奧里亞文、泰盧固文或泰文的文字顯示方式一致，且日後不會出錯。

針對指定 Android 14 (API 級別 34) 以下版本的應用程式，或指定 Android 15 (API 級別 35) 但將 elegantTextHeight 屬性設為 false，藉此覆寫預設行為的應用程式，

如果應用程式指定 Android 16 (API 級別 36)，或指定 Android 15 (API 級別 35) 但未將 elegantTextHeight 屬性設為 false 來覆寫預設值，則會採用

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

在大型螢幕裝置上顯示應用程式時，Android 16 (API 級別 36) 會進行下列變更。

自動調整式版面配置

Android 應用程式現在可在各種裝置上執行 (例如手機、平板電腦、折疊式裝置、桌機、車輛和電視)，且大螢幕提供多種視窗模式 (例如分割畫面和桌機視窗)，因此開發人員應建構可適應任何螢幕和視窗大小的 Android 應用程式，無論裝置方向為何。在現今多裝置的世界中，限制螢幕方向和大小調整等範例過於嚴苛。

忽略螢幕方向、是否可調整大小和顯示比例限制

如果應用程式指定 Android 16 (API 級別 36) 為目標，Android 16 會變更系統管理螢幕方向、大小調整功能和長寬比限制的方式。如果螢幕的最小寬度 >= 600dp，就不再適用這些限制。應用程式也會填滿整個顯示視窗，無論長寬比或使用者偏好的螢幕方向為何，都不會出現側邊黑邊。

這項異動會導入新的標準平台行為。Android 正在朝向應用程式可適應各種螢幕方向、大小和顯示比例的模型發展。固定螢幕方向或限制尺寸調整等限制會阻礙應用程式的適應性，因此建議讓應用程式具備適應性，提供最佳使用者體驗。

您也可以使用應用程式相容性架構，並啟用 UNIVERSAL_RESIZABLE_BY_DEFAULT 相容性標記，測試這項行為。

常見的破壞性變更

忽略方向、大小調整和長寬比限制，可能會影響應用程式在某些裝置上的 UI，尤其是專為鎖定直向的小版面配置設計的元素，例如版面配置遭到延展，以及動畫和元件超出螢幕範圍等問題。如果對顯示比例或螢幕方向做出任何假設，可能會導致應用程式出現視覺問題。請參閱這篇文章，進一步瞭解如何避免這類問題，並改善應用程式的適應性行為。

允許裝置旋轉會導致更多活動重建，如果未妥善保留，可能會導致使用者狀態遺失。如要瞭解如何正確儲存 UI 狀態，請參閱「儲存 UI 狀態」。

導入作業詳細資料

在全螢幕和多視窗模式下，大型螢幕裝置會忽略下列資訊清單屬性和執行階段 API：

• screenOrientation
• resizableActivity
• minAspectRatio
• maxAspectRatio
• setRequestedOrientation()
• getRequestedOrientation()

系統會忽略 screenOrientation、setRequestedOrientation() 和 getRequestedOrientation() 的下列值：

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

就螢幕大小調整功能而言，android:resizeableActivity="false"、android:minAspectRatio 和 android:maxAspectRatio 沒有影響。

如果應用程式以 Android 16 (API 級別 36) 為目標，系統預設會忽略大螢幕上的應用程式方向、大小調整和長寬比限制，但每個尚未完全準備就緒的應用程式都可以暫時選擇停用這項行為 (這會導致應用程式進入相容性模式)。

例外狀況

在下列情況中，Android 16 的螢幕方向、大小調整和長寬比限制不適用：

• 遊戲 (根據 android:appCategory 旗標)
• 使用者在裝置的顯示比例設定中，明確選擇採用應用程式的預設行為
• 小於 sw600dp 的螢幕

暫時退出

如要選擇不記錄特定活動，請宣告 PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY 資訊清單屬性：

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

如果應用程式有太多部分尚未支援 Android 16，您可以在應用程式層級套用相同屬性，完全停用這項功能：

<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) 包含下列與健康和健身資料相關的變更。

健康與健身權限

For apps targeting Android 16 (API level 36) or higher, BODY_SENSORS permissions use more granular permissions under android.permissions.health, which Health Connect also uses. As of Android 16, any API previously requiring BODY_SENSORS or BODY_SENSORS_BACKGROUND requires the corresponding android.permissions.health permission instead. This affects the following data types, APIs, and foreground service types:

• HEART_RATE_BPM from Health Services on Wear OS
• Sensor.TYPE_HEART_RATE from Android Sensor Manager
• heartRateAccuracy and heartRateBpm from ProtoLayout on Wear OS
• FOREGROUND_SERVICE_TYPE_HEALTH where the respective android.permission.health permission is needed in place of BODY_SENSORS

If your app uses these APIs, it should request the respective granular permissions:

• For while-in-use monitoring of Heart Rate, SpO2, or Skin Temperature: request the granular permission under android.permissions.health, such as READ_HEART_RATE instead of BODY_SENSORS.
• For background sensor access: request READ_HEALTH_DATA_IN_BACKGROUND instead of BODY_SENSORS_BACKGROUND.

These permissions are the same as those that guard access to reading data from Health Connect, the Android datastore for health, fitness, and wellness data.

Mobile apps

Mobile apps migrating to use the READ_HEART_RATE and other granular permissions must also declare an activity to display the app's privacy policy. This is the same requirement as Health Connect.

連線能力

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

處理債券遺失和加密變更的新意圖

除了改善連結遺失處理功能，Android 16 也推出了 2 個新的意圖，讓應用程式更能察覺連結遺失和加密變更。

鎖定 Android 16 的應用程式現在可以：

• 在偵測到遠端連結中斷時接收 ACTION_KEY_MISSING 意圖，以便提供更有用的使用者意見回饋，並採取適當行動。
• 每當連結的加密狀態變更時，就會收到 ACTION_ENCRYPTION_CHANGE 意圖。包括加密狀態變更、加密演算法變更和加密金鑰大小變更。如果應用程式稍後收到 ACTION_ENCRYPTION_CHANGE 意圖，且連結已成功加密，則必須考慮恢復連結。

因應不同原始設備製造商 (OEM) 實作

雖然 Android 16 推出了這些新意圖，但不同裝置製造商 (OEM) 的實作和廣播方式可能有所不同。為確保應用程式可在所有裝置上提供一致且可靠的體驗，開發人員應設計連結中斷處理機制，以便妥善因應這些潛在的變化。

我們建議您採用下列應用程式行為：

• 如果廣播 ACTION_KEY_MISSING 意圖：

  系統會中斷 ACL (非同步無連結) 連結，但會保留裝置的連結資訊 (如這裡所述)。

  應用程式應使用這個意圖做為偵測連結中斷的主要信號，並在啟動裝置忘記或重新配對功能前，引導使用者確認遠端裝置是否在範圍內。

  如果裝置在收到 ACTION_KEY_MISSING 後中斷連線，應用程式應謹慎重新連線，因為裝置可能已不再與系統綁定。

• 如果 ACTION_KEY_MISSING 意圖未廣播：

  ACL 連結會保持連線狀態，系統會移除裝置的連結資訊，這與 Android 15 的行為相同。

  在這種情況下，應用程式應繼續使用與先前 Android 版本相同的現有連結失效處理機制，以偵測及管理連結失效事件。

移除藍牙配對的新方式

All apps targeting Android 16 are now able to unpair bluetooth devices using a public API in CompanionDeviceManager. If a companion device is being managed as a CDM association, then the app can trigger bluetooth bond removal by using the new removeBond(int) API on the associated device. The app can monitor the bond state changes by listening to the bluetooth device broadcast event ACTION_BOND_STATE_CHANGED.

安全性

Android 16 (API 級別 36) 包含下列安全性異動。

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:

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) 包含下列隱私權異動。

區域網路權限

Devices on the LAN can be accessed by any app that has the INTERNET permission. This makes it easy for apps to connect to local devices but it also has privacy implications such as forming a fingerprint of the user, and being a proxy for location.

The Local Network Protections project aims to protect the user's privacy by gating access to the local network behind a new runtime permission.

Release plan

This change will be deployed between two releases, 25Q2 and TBD respectively. It is imperative that developers follow this guidance for 25Q2 and share feedback because these protections will be enforced at a later Android release. Moreover, they will need to update scenarios which depend on implicit local network access by using the following guidance and prepare for user rejection and revocation of the new permission.

Impact

At the current stage, LNP is an opt-in feature which means only the apps that opt in will be affected. The goal of the opt-in phase is for app developers to understand which parts of their app depend on implicit local network access such that they can prepare to permission guard them for the next release.

Apps will be affected if they access the user's local network using:

• Direct or library use of raw sockets on local network addresses (e.g. mDNS or SSDP service discovery protocol)
• Use of framework level classes that access the local network (e.g. NsdManager)

Traffic to and from a local network address requires local network access permission. The following table lists some common cases:

These restrictions are implemented deep in the networking stack, and thus they apply to all networking APIs. This includes sockets created in native or managed code, networking libraries like Cronet and OkHttp, and any APIs implemented on top of those. Trying to resolve services on the local network (i.e. those with a .local suffix) will require local network permission.

Exceptions to the rules above:

• If a device's DNS server is on a local network, traffic to or from it (at port 53) doesn't require local network access permission.
• Applications using Output Switcher as their in-app picker won't need local network permissions (more guidance to come in 2025Q4).

Developer Guidance (Opt-in)

To opt into local network restrictions, do the following:

1. Flash the device to a build with 25Q2 Beta 3 or later.
2. Install the app to be tested.

3. Toggle the Appcompat flag in adb:

   adb shell am compat enable RESTRICT_LOCAL_NETWORK <package_name>
   

4. Reboot The device

Now your app's access to the local network is restricted and any attempt to access the local network will lead to socket errors. If you are using APIs that perform local network operations outside of your app process (ex: NsdManager), they won't be impacted during the opt-in phase.

To restore access, you must grant your app permission to NEARBY_WIFI_DEVICES.

1. Ensure the app declares the NEARBY_WIFI_DEVICES permission in its manifest.
2. Go to Settings > Apps > [Application Name] > Permissions > Nearby devices > Allow.

Now your app's access to the local network should be restored and all your scenarios should work as they did prior to opting the app in.

Once enforcement for local network protection begins, here is how the app network traffic will be impacted.

Use the following command to toggle-off the App-Compat flag

adb shell am compat disable RESTRICT_LOCAL_NETWORK <package_name>

Errors

Errors arising from these restrictions will be returned to the calling socket whenever it invokes send or a send variant to a local network address.

Example errors:

sendto failed: EPERM (Operation not permitted)

sendto failed: ECONNABORTED (Operation not permitted)

Local Network Definition

A local network in this project refers to an IP network that utilizes a broadcast-capable network interface, such as Wi-Fi or Ethernet, but excludes cellular (WWAN) or VPN connections.

The following are considered local networks:

IPv4:

• 169.254.0.0/16 // Link Local
• 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:

• Link-local
• Directly-connected routes
• Stub networks like Thread
• Multiple-subnets (TBD)

Additionally, both multicast addresses (224.0.0.0/4, ff00::/8) and the IPv4 broadcast address (255.255.255.255) are classified as local network addresses.

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。