功能與 API 總覽

Android 14 為開發人員推出了強大的功能和 API。以下各節可協助您瞭解應用程式功能，並開始使用相關的 API。

如需新增、修改及移除 API 的詳細清單，請參閱 API 差異比較表。如要進一步瞭解新增的 API，請參閱 Android API 參考資料。在 Android 14 中，請尋找 API 級別 34 新增的 API。如要瞭解平台變更可能對應用程式造成的影響，請務必查看指定 Android 14 的應用程式和所有應用程式的 Android 14 行為變更。

國際化

個別應用程式語言偏好

Android 14 進一步延伸 Android 13 (API 級別 33) 所推出的個別應用程式語言功能，並新增多項功能：

• 自動產生應用程式的 localeConfig：自 Android Studio Giraffe Canary 7 和 AGP 8.1.0-alpha07 起，您可以將應用程式設為自動支援個別應用程式語言偏好設定。Android Gradle 外掛程式會根據您的專案資源產生 LocaleConfig 檔案，並在最終資訊清單檔案中為該檔案新增參照，為您省去手動建立或更新檔案的需求。AGP 會使用應用程式模組 res 資料夾中的資源和任何程式庫模組依附元件，以決定要納入 LocaleConfig 檔案的語言代碼。

• 應用程式 localeConfig 的動態更新：請使用 法LocaleManager 中的 setOverrideLocaleConfig() 和 getOverrideLocaleConfig() 方法，以動態方式更新應用程式在裝置的系統設定中的支援語言清單。如果應用程式使用伺服器端推送進行本地化，則可利用此彈性自訂各區域的支援語言清單、執行 A/B 實驗，或提供更新的語言代碼清單。

• 輸入法編輯器 (IME) 的應用程式語言瀏覽權限：輸入法編輯器可透過 getApplicationLocales() 方法檢查當前應用程式的語言，並和輸入法編輯器的語言進行比對。

文法轉變 API

30 億人使用性別化語言：即名詞、動詞、形容詞和介系詞會隨著交談或談論對象或目標的性別，而有不同變化形式的文法類別語言。一般來說，許多性別化語言都會使用陽性文法性別做為預設或通用性別。

若以錯誤的文法性別稱呼使用者，例如：以陽性文法性別稱呼女性，可能會對其表現及態度產生負面影響。相較之下，如果使用者介面的用語正確反映了使用者的文法性別，便可提高使用者參與度，同時提供更個人化且更自然親切的使用者體驗。

為了協助你針對使用文法性別的語言，建構以使用者為中心的使用者介面，Android 14 採用了文法轉變 API，可讓你新增對文法性別的支援，而不必重構應用程式。

地區偏好設定

Regional preferences enable users to personalize temperature units, the first day of the week, and numbering systems. A European living in the United States might prefer temperature units to be in Celsius rather than Fahrenheit and for apps to treat Monday as the beginning of the week instead of the US default of Sunday.

New Android Settings menus for these preferences provide users with a discoverable and centralized location to change app preferences. These preferences also persist through backup and restore. Several APIs and intents—such as getTemperatureUnit and getFirstDayOfWeek— grant your app read access to user preferences, so your app can adjust how it displays information. You can also register a BroadcastReceiver on ACTION_LOCALE_CHANGED to handle locale configuration changes when regional preferences change.

To find these settings, open the Settings app and navigate to System > Languages & input > Regional preferences.

Regional preferences screen in Android system settings.

Temperature options for regional preferences in Android system settings.

無障礙設定

非線性字型縮放至 200%

自 Android 14 起，系統將支援高達 200% 的字型縮放功能，提供 視力不佳的使用者提供額外的無障礙服務選項， 無障礙內容規範 (WCAG)。

為避免畫面上的大型文字元素縮放過大，系統會採用系統做法 會套用非線性縮放曲線此縮放策略指的是大型文字 因此未像較小的文字一樣縮放非線性字型縮放功能 保留不同大小元素之間的比例階層 減少線性文字縮放為高角度的問題 (例如 截斷或因為超大型顯示而難以閱讀的文字 大小)。

使用非線性字型縮放測試應用程式

如果您已使用經過調整像素 (sp) 的單位定義文字大小，系統會自動將這些額外選項和縮放改善功能套用至應用程式中的文字。不過，您仍應啟用最大字型大小 (200%) 執行 UI 測試，確保應用程式能正確套用字型大小，並在不影響可用性的情況下，因應更大的字型大小。

如要啟用 200% 的字型大小，請按照下列步驟操作：

1. 開啟「設定」應用程式，然後依序前往「無障礙中心」>「無障礙設定」顯示大小和 文字。
2. 在「字型大小」選項中，輕觸加號 (+) 圖示，直到達字型大小上限為止，如本節隨附的圖片所示。

使用經過調整像素 (sp) 的單位處理文字大小

請記得一律以 sp 單位為單位指定文字大小。時間 應用程式使用 sp 單位，Android 可套用使用者偏好的文字大小 彈性調整資源配置

請勿使用 sp 單位做為邊框間距，也不應以隱含邊框間距來定義檢視畫面高度： 非線性字型縮放 sp 尺寸比例可能不一致，因此 4sp + 20sp 不一定等於 24sp。

轉換經過調整像素 (sp) 的單位

使用 TypedValue.applyDimension() 將 sp 單位轉換為像素，並使用 TypedValue.deriveDimension() 將像素轉換為 sp。這些方法會自動套用至適當的非線性縮放曲線。

避免使用硬式編碼方程式 Configuration.fontScale 或 DisplayMetrics.scaledDensity。因為字型縮放功能 非線性，scaledDensity 欄位已不準確。由於字型不再以單一標量值進行縮放，因此 fontScale 欄位應僅用於提供資訊。

使用 sp 單位處理 lineHeight

一律改用 sp 單位定義 android:lineHeight 因此，行高會隨著文字縮放。否則，如果您的文字 是 sp，但 lineHeight 的單位為 dp 或 px，則不會縮放，看起來會受到限制。 TextView 會自動修正 lineHeight，使其符合您的預期 只有在 textSize 和 lineHeight 都同時符合時，比例才會保留 以 sp 為單位定義。

相機和媒體

圖片的 Ultra HDR

Android 14 新增了對高動態範圍 (HDR) 圖片的支援，可在拍攝相片時保留更多感應器資訊，進而呈現鮮豔的色彩和更強烈的對比。Android 使用 Ultra HDR 格式，可與 JPEG 圖片完全相容，讓應用程式與 HDR 圖片無縫互動，並視需要以標準動態範圍 (SDR) 顯示。

當應用程式選擇為活動視窗使用 HDR UI (透過資訊清單項目或在執行階段呼叫 Window.setColorMode())，架構會自動在 UI 中以 HDR 格式轉譯這些圖片。您也可以在支援的裝置上拍攝壓縮的超高動態範圍靜態圖片。感應器可復原更多顏色，因此後製編輯的彈性更高。與 Ultra HDR 影像相關聯的 Gainmap 可用於使用 OpenGL 或 Vulkan 轉譯這些影像。

相機擴充功能中的變焦、對焦、後製預覽等功能

Android 14 upgrades and improves camera extensions, allowing apps to handle longer processing times, which enables improved images using compute-intensive algorithms like low-light photography on supported devices. These features give users an even more robust experience when using camera extension capabilities. Examples of these improvements include:

• Dynamic still capture processing latency estimation provides much more accurate still capture latency estimates based on the current scene and environment conditions. Call CameraExtensionSession.getRealtimeStillCaptureLatency() to get a StillCaptureLatency object that has two latency estimation methods. The getCaptureLatency() method returns the estimated latency between onCaptureStarted and onCaptureProcessStarted(), and the getProcessingLatency() method returns the estimated latency between onCaptureProcessStarted() and the final processed frame being available.
• Support for capture progress callbacks so that apps can display the current progress of long-running, still-capture processing operations. You can check if this feature is available with CameraExtensionCharacteristics.isCaptureProcessProgressAvailable, and if it is, you implement the onCaptureProcessProgressed() callback, which has the progress (from 0 to 100) passed in as a parameter.

• Extension specific metadata, such as CaptureRequest.EXTENSION_STRENGTH for dialing in the amount of an extension effect, such as the amount of background blur with EXTENSION_BOKEH.

• Postview Feature for Still Capture in camera extensions, which provides a less-processed image more quickly than the final image. If an extension has increased processing latency, a postview image could be provided as a placeholder to improve UX and switched out later for the final image. You can check if this feature is available with CameraExtensionCharacteristics.isPostviewAvailable. Then you can pass an OutputConfiguration to ExtensionSessionConfiguration.setPostviewOutputConfiguration.

• Support for SurfaceView allowing for a more optimized and power-efficient preview render path.

• Support for tap to focus and zoom during extension usage.

感應器內變焦

當 CameraCharacteristics 中的 REQUEST_AVAILABLE_CAPABILITIES_STREAM_USE_CASE 包含 SCALER_AVAILABLE_STREAM_USE_CASES_CROPPED_RAW 時，應用程式可以使用進階感應器功能，透過 CaptureRequest 和 RAW 目標 (其串流用途已設為 CameraMetadata.SCALER_AVAILABLE_STREAM_USE_CASES_CROPPED_RAW)，為經裁剪的 RAW 串流提供與全景視野相同的像素。透過實作要求覆寫控制項，更新後的相機可在其他相機控制項準備就緒前，提供縮放控制選項。

無損 USB 音訊

Android 14 gains support for lossless audio formats for audiophile-level experiences over USB wired headsets. You can query a USB device for its preferred mixer attributes, register a listener for changes in preferred mixer attributes, and configure mixer attributes using the AudioMixerAttributes class. This class represents the format, such as channel mask, sample rate, and behavior of the audio mixer. The class allows for audio to be sent directly, without mixing, volume adjustment, or processing effects.

開發人員工作效率和工具

Credential Manager

Android 14 會新增 Credential Manager 做為平台 API，並透過使用 Google Play 服務的 Jetpack 程式庫，進一步支援 Android 4.4 (API 級別 19) 裝置。Credential Manager 的目標是透過 API 協助使用者輕鬆登入，這些 API 會透過使用者設定的憑證提供者擷取及儲存憑證。Credential Manager 可在單一 API 中支援多種登入方式，包括使用者名稱和密碼、密碼金鑰，以及聯合登入解決方案 (例如使用 Google 帳戶登入)。

密碼金鑰具有許多優點，舉例來說，密碼金鑰採用業界標準，可在不同作業系統和瀏覽器環境中運作，也能與網站和應用程式搭配使用。

如需更多資訊，請參閱 Credential Manager 和密碼金鑰說明文件，以及Credential Manager 和密碼金鑰相關網誌文章。

Health Connect

Health Connect is an on-device repository for user health and fitness data. It allows users to share data between their favorite apps, with a single place to control what data they want to share with these apps.

On devices running Android versions prior to Android 14, Health Connect is available to download as an app on the Google Play store. Starting with Android 14, Health Connect is part of the platform and receives updates through Google Play system updates without requiring a separate download. With this, Health Connect can be updated frequently, and your apps can rely on Health Connect being available on devices running Android 14 or higher. Users can access Health Connect from the Settings in their device, with privacy controls integrated into the system settings.

Users can get started using Health Connect without a separate app download on devices running Android 14 or higher.

Users can control which apps have access to their health and fitness data through system settings.

Health Connect includes several new features in Android 14, such as exercise routes, allowing users to share a route of their workout which can be visualized on a map. A route is defined as a list of locations saved within a window of time, and your app can insert routes into exercise sessions, tying them together. To ensure that users have complete control over this sensitive data, users must allow sharing individual routes with other apps.

For more information, see the Health Connection documentation and the blogpost on What's new in Android Health.

OpenJDK 17 更新

Android 14 持續更新 Android 核心程式庫，以便與最新版 OpenJDK LTS 中的功能保持一致，其中包括程式庫更新以及應用程式與平台開發人員的 Java 17 語言支援。

新功能和改善項目如下：

• 已將約 300 個 java.base 類別更新至可支援 Java 17。
• 文字模塊已針對 Java 程式設計語言推出多行字串常值。
• instanceof 的模式比對可讓您在 instanceof 中，不需要使用其他變數，即可將物件視為具有特定類型處理。
• 密封類別可讓您限制可進行擴充或實作的類別與介面。

進行 Google Play 系統更新 (Mainline 計畫) 之後，超過 6 億部裝置將可收到包含這些變更的最新 Android 執行階段 (ART) 更新。這是我們承諾的一部分，讓應用程式在各種裝置上都能夠擁有更一致、安全的環境，同時為各平台版本的使用者提供新的功能與能力。

Java 和 OpenJDK 是 Oracle 和/或其關係企業的商標或註冊商標。

應用程式商店改善項目

Android 14 introduces several PackageInstaller APIs that allow app stores to improve their user experience.

Request install approval before downloading

Installing or updating an app might require user approval. For example, when an installer making use of the REQUEST_INSTALL_PACKAGES permission attempts to install a new app. In prior Android versions, app stores can only request user approval after APKs are written to the install session and the session is committed.

Starting with Android 14, the requestUserPreapproval() method lets installers request user approval before committing the install session. This improvement lets an app store defer downloading any APKs until after the installation has been approved by the user. Furthermore, once a user has approved installation, the app store can download and install the app in the background without interrupting the user.

Claim responsibility for future updates

The setRequestUpdateOwnership() method allows an installer to indicate to the system that it intends to be responsible for future updates to an app it is installing. This capability enables update ownership enforcement, meaning that only the update owner is permitted to install automatic updates to the app. Update ownership enforcement helps to ensure that users receive updates only from the expected app store.

Any other installer, including those making use of the INSTALL_PACKAGES permission, must receive explicit user approval in order to install an update. If a user decides to proceed with an update from another source, update ownership is lost.

Update apps at less-disruptive times

App stores typically want to avoid updating an app that is actively in use because this leads to the app's running processes being killed, which potentially interrupts what the user was doing.

Starting with Android 14, the InstallConstraints API gives installers a way to ensure that their app updates happen at an opportune moment. For example, an app store can call the commitSessionAfterInstallConstraintsAreMet() method to make sure that an update is only committed when the user is no longer interacting with the app in question.

Seamlessly install optional splits

With split APKs, features of an app can be delivered in separate APK files, rather than as a monolithic APK. Split APKs allow app stores to optimize the delivery of different app components. For example, app stores might optimize based on the properties of the target device. The PackageInstaller API has supported splits since its introduction in API level 22.

In Android 14, the setDontKillApp() method allows an installer to indicate that the app's running processes shouldn't be killed when new splits are installed. App stores can use this feature to seamlessly install new features of an app while the user is using the app.

應用程式中繼資料套件

Starting in Android 14, the Android package installer lets you specify app metadata, such as data safety practices, to include on app store pages such as Google Play.

在使用者擷取裝置螢幕畫面時偵測

為建立更標準化的螢幕截圖偵測體驗，Android 14 推出了具隱私保護功能的螢幕截圖偵測 API。此 API 可讓應用程式依個別活動登錄回呼。當使用者在具備瀏覽權限的活動中拍攝螢幕截圖時，系統會叫用這些回呼，並傳送通知給使用者。

使用者體驗

Sharesheet 自訂動作與改善排名

Android 14 會更新系統 Sharesheet，以支援自訂應用程式動作，使用者也能取得更豐富的預覽結果。

新增自訂動作

在 Android 14 中，應用程式可將自訂動作新增至其叫用的系統 Sharesheet。

改善直接分享目標的排名

Android 14 會使用更多應用程式信號來判斷直接分享目標的排名，以便為使用者提供更實用的結果。如要提供最實用的信號來提升排名，請按照提升直接分享目標排名的相關指南操作。通訊應用程式也可以回報捷徑使用情形，包括傳送和接收的訊息。

所示

支援預測返回功能的內建和自訂動畫

Android 13 introduced the predictive back-to-home animation behind a developer option. When used in a supported app with the developer option enabled, swiping back shows an animation indicating that the back gesture exits the app back to the home screen.

Android 14 includes multiple improvements and new guidance for Predictive Back:

• You can set android:enableOnBackInvokedCallback=true to opt in to predictive back system animations per-Activity instead of for the entire app.
• We've added new system animations to accompany the back-to-home animation from Android 13. The new system animations are cross-activity and cross-task, which you get automatically after migrating to Predictive Back.
• We've added new Material Component animations for Bottom sheets, Side sheets, and Search.
• We've created design guidance for creating custom in-app animations and transitions.
• We've added new APIs to support custom in-app transition animations:
  • handleOnBackStarted, handleOnBackProgressed, handleOnBackCancelled in OnBackPressedCallback
  • onBackStarted, onBackProgressed, onBackCancelled in OnBackAnimationCallback
  • Use overrideActivityTransition instead of overridePendingTransition for transitions that respond as the user swipes back.

With this Android 14 preview release, all features of Predictive Back remain behind a developer option. See the developer guide to migrate your app to predictive back, as well as the developer guide to creating custom in-app transitions.

大螢幕裝置製造商個別應用程式覆寫值

Per-app overrides enable device manufacturers to change the behavior of apps on large screen devices. For example, the FORCE_RESIZE_APP override instructs the system to resize the app to fit display dimensions (avoiding size compatibility mode) even if resizeableActivity="false" is set in the app manifest.

Overrides are intended to improve the user experience on large screens.

New manifest properties enable you to disable some device manufacturer overrides for your app.

大螢幕使用者個別應用程式覆寫值

Per-app overrides change the behavior of apps on large screen devices. For example, the OVERRIDE_MIN_ASPECT_RATIO_LARGE device manufacturer override sets the app aspect ratio to 16:9 regardless of the app's configuration.

Android 14 QPR1 enables users to apply per‑app overrides by means of a new settings menu on large screen devices.

應用程式分享螢幕畫面

分享應用程式畫面功能可讓使用者在錄製螢幕內容時，分享應用程式視窗，而非整個裝置畫面。

透過應用程式螢幕分享功能，系統會從共用畫面中排除狀態列、導覽列、通知和其他系統 UI 元素。只會分享所選應用程式的內容。

應用程式螢幕分享功能可讓使用者執行多個應用程式，但只分享單一應用程式的內容，進而提升工作效率和隱私權。

Pixel 8 Pro 的 Gboard 支援 LLM 智慧回覆功能

在搭載 12 月功能更新的 Pixel 8 Pro 裝置上，開發人員可以試用 Gboard 中採用 Google Tensor 晶片的大型語言模型 (LLM) 所提供的更高品質智慧回覆功能。

這項功能目前僅在 WhatsApp、Line 和 KakaoTalk 提供美式英文的限量預覽版。你必須使用 Pixel 8 Pro 裝置，並將 Gboard 做為鍵盤。

如要試用這項功能，請先依序前往「設定」>「開發人員選項」>「AI Core 設定」>「啟用 Aicore 持續性」。

接著，在支援的應用程式中開啟對話，即可在 Gboard 的建議列中看到 LLM 支援的智慧回覆功能，以回覆傳入的訊息。

圖形

路徑可供查詢及內插

Android's Path API is a powerful and flexible mechanism for creating and rendering vector graphics, with the ability to stroke or fill a path, construct a path from line segments or quadratic or cubic curves, perform boolean operations to get even more complex shapes, or all of these simultaneously. One limitation is the ability to find out what is actually in a Path object; the internals of the object are opaque to callers after creation.

To create a Path, you call methods such as moveTo(), lineTo(), and cubicTo() to add path segments. But there has been no way to ask that path what the segments are, so you must retain that information at creation time.

Starting in Android 14, you can query paths to find out what's inside of them. First, you need to get a PathIterator object using the Path.getPathIterator API:

val path = Path().apply {
    moveTo(1.0f, 1.0f)
    lineTo(2.0f, 2.0f)
    close()
}
val pathIterator = path.pathIterator

Path path = new Path();
path.moveTo(1.0F, 1.0F);
path.lineTo(2.0F, 2.0F);
path.close();
PathIterator pathIterator = path.getPathIterator();

Next, you can call PathIterator to iterate through the segments one by one, retrieving all of the necessary data for each segment. This example uses PathIterator.Segment objects, which packages up the data for you:

for (segment in pathIterator) {
    println("segment: ${segment.verb}, ${segment.points}")
}

while (pathIterator.hasNext()) {
    PathIterator.Segment segment = pathIterator.next();
    Log.i(LOG_TAG, "segment: " + segment.getVerb() + ", " + segment.getPoints());
}

PathIterator also has a non-allocating version of next() where you can pass in a buffer to hold the point data.

One of the important use cases of querying Path data is interpolation. For example, you might want to animate (or morph) between two different paths. To further simplify that use case, Android 14 also includes the interpolate() method on Path. Assuming the two paths have the same internal structure, the interpolate() method creates a new Path with that interpolated result. This example returns a path whose shape is halfway (a linear interpolation of .5) between path and otherPath:

val interpolatedResult = Path()
if (path.isInterpolatable(otherPath)) {
    path.interpolate(otherPath, .5f, interpolatedResult)
}

Path interpolatedResult = new Path();
if (path.isInterpolatable(otherPath)) {
    path.interpolate(otherPath, 0.5F, interpolatedResult);
}

The Jetpack graphics-path library enables similar APIs for earlier versions of Android as well.

使用頂點和片段著色器的自訂網格

Android 一直支援使用自訂著色繪製三角形網格，但輸入網格格式僅限於少數預先定義的屬性組合。Android 14 新增了自訂網格支援功能，可將其定義為 三角形 或 三角形條，並視需要編入索引。這些網格會使用自訂屬性、頂點步幅、變化，以及以 AGSL 編寫的頂點和片段著色器指定。

頂點著色器會定義變化，例如位置和顏色，而片段著色器則可選擇定義像素的顏色，通常是使用頂點著色器建立的變化。如果片段著色器提供顏色，系統會使用繪製網格時選取的混合模式，將該顏色與目前的 Paint 顏色混合。統一變數可傳遞至片段和頂點著色器，以提供更多彈性。

Canvas 的硬體緩衝區轉譯器

To assist in using Android's Canvas API to draw with hardware acceleration into a HardwareBuffer, Android 14 introduces HardwareBufferRenderer. This API is particularly useful when your use case involves communication with the system compositor through SurfaceControl for low-latency drawing.