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。

無邊框螢幕停用選項即將移除

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, 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.

必須遷移或停用預測返回手勢

For apps targeting Android 16 (API level 36) or higher and running on an Android 16 or higher device, the predictive back system animations (back-to-home, cross-task, and cross-activity) are enabled by default. Additionally, onBackPressed is not called and KeyEvent.KEYCODE_BACK is not dispatched anymore.

If your app intercepts the back event and you haven't migrated to predictive back yet, update your app to use supported back navigation APIs, or temporarily opt out by setting the android:enableOnBackInvokedCallback attribute to false in the <application> or <activity> tag of your app's AndroidManifest.xml file.

優雅字型 API 已淘汰並停用

Apps targeting Android 15 (API level 35) have the elegantTextHeight TextView attribute set to true by default, replacing the compact font with one that is much more readable. You could override this by setting the elegantTextHeight attribute to false.

Android 16 deprecates the elegantTextHeight attribute, and the attribute will be ignored once your app targets Android 16. The "UI fonts" controlled by these APIs are being discontinued, so you should adapt any layouts to ensure consistent and future proof text rendering in Arabic, Lao, Myanmar, Tamil, Gujarati, Kannada, Malayalam, Odia, Telugu or Thai.

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

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:

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

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

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

針對指定 Android 16 以上版本的應用程式，MediaStore#getVersion() 現已成為每個應用程式的專屬值。這麼做可移除版本字串中的識別屬性，以免遭到濫用，並防止用於指紋辨識技術。應用程式不應對此版本的格式做出任何假設。應用程式在使用此 API 時應已處理版本變更，且在大多數情況下，不必變更目前的行為，除非開發人員嘗試推斷超出此 API 預期範圍的其他資訊。

更安全的意圖

「更安全的意圖」功能是一項多階段安全措施，旨在提升 Android 意圖解析機制的安全性。目標是在意圖處理期間新增檢查，並篩除不符合特定條件的意圖，藉此保護應用程式免於惡意行為。

在 Android 15 中，這項功能著重於傳送應用程式，現在 Android 16 則將控制權轉移至接收應用程式，讓開發人員使用應用程式資訊清單選擇加入嚴格的 Intent 解析。

我們將實施兩項重大變更：

1. 明確意圖必須與目標元件的意圖篩選器相符：如果意圖明確指定元件，就應與該元件的意圖篩選器相符。

2. 沒有動作的意圖無法與任何意圖篩選器相符：如果意圖未指定動作，就不應解析至任何意圖篩選器。

這些變更只會在涉及多個應用程式時生效，不會影響單一應用程式內的意圖處理程序。

影響

由於這項功能採選擇啟用制，開發人員必須在應用程式資訊清單中明確啟用，才會生效。因此，這項功能只會影響開發人員符合下列條件的應用程式：

• 瞭解 Safer Intents 功能及其優點。
• 主動選擇在應用程式中採用更嚴格的意圖處理做法。

這種選擇加入的做法可將風險降到最低，避免現有應用程式因依賴目前安全性較低的意圖解析行為而無法運作。

雖然 Safer Intents 計畫在 Android 16 的初期影響可能有限，但這項計畫的發展藍圖涵蓋更廣泛的影響，未來將在 Android 版本中發揮作用。我們最終會將嚴格意圖解析設為預設行為。

Safer Intents 功能可讓惡意應用程式更難以利用 Intent 解析機制中的漏洞，因此有助於大幅提升 Android 生態系統的安全性。

不過，為解決現有應用程式的潛在相容性問題，我們必須謹慎管理選擇停用和強制執行的過渡期。

實作

開發人員必須在應用程式資訊清單中使用 intentMatchingFlags 屬性，明確啟用更嚴格的意圖比對。以下範例說明如何為整個應用程式啟用這項功能，但針對接收器停用/停用這項功能：

<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>

支援的標記詳細說明：

測試與偵錯

強制執行功能啟用後，如果意圖呼叫端已正確填入意圖，應用程式應可正常運作。不過，遭封鎖的 Intent 會觸發警告記錄訊息，例如 "Intent does not match component's intent filter:" 和 "Access blocked:"，並附上 "PackageManager." 標記。這表示可能存在影響應用程式的問題，需要特別注意。

Logcat 篩選器：

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

When prompted for photo and video permissions by an app targeting SDK 36 or higher on devices running Android 16 or higher, users who choose to limit access to selected media will see any photos owned by the app pre-selected in the photo picker. Users can deselect any of these pre-selected items, which will revoke the app's access to those photos and videos.