Panoramica delle funzionalità e delle API

Android 14 introduce fantastiche funzionalità e API per gli sviluppatori. Di seguito puoi trovare informazioni sulle funzionalità per le tue app e iniziare a utilizzare le API correlate.

Per un elenco dettagliato delle API aggiunte, modificate e rimosse, leggi il report sulle differenze delle API. Per informazioni dettagliate sulle API aggiunte, consulta il riferimento all'API Android. Per Android 14, cerca le API aggiunte nel livello API 34. Per scoprire le aree in cui le modifiche alla piattaforma potrebbero influire sulle tue app, consulta le modifiche al comportamento di Android 14 per le app che hanno come target Android 14 e per tutte le app.

Internazionalizzazione

Lingua preferita nelle app

Android 14 expands on the per-app language features that were introduced in Android 13 (API level 33) with these additional capabilities:

  • Automatically generate an app's localeConfig: Starting with Android Studio Giraffe Canary 7 and AGP 8.1.0-alpha07, you can configure your app to support per-app language preferences automatically. Based on your project resources, the Android Gradle plugin generates the LocaleConfig file and adds a reference to it in the final manifest file, so you no longer have to create or update the file manually. AGP uses the resources in the res folders of your app modules and any library module dependencies to determine the locales to include in the LocaleConfig file.

  • Dynamic updates for an app's localeConfig: Use the setOverrideLocaleConfig() and getOverrideLocaleConfig() methods in LocaleManager to dynamically update your app's list of supported languages in the device's system settings. Use this flexibility to customize the list of supported languages per region, run A/B experiments, or provide an updated list of locales if your app utilizes server-side pushes for localization.

  • App language visibility for input method editors (IMEs): IMEs can utilize the getApplicationLocales() method to check the language of the current app and match the IME language to that language.

API Grammatical Inflection

有 30 亿人在使用区分性别的语言，此类语言的语法类别（例如名词、动词、形容词和介词）会根据您交谈所涉及的人或物的性别而变化。传统上，许多区分性别的语言使用阳性语法性别作为默认或通用性别。

以错误的语法性别来称呼用户，例如以阳性语法性别来称呼女性，可能会对她们的表现和态度产生负面影响。相比之下，界面语言如果能正确反映用户的语法性别，就可以提高用户互动度，并提供更个性化、更自然的用户体验。

To help you build a user-centric UI for gendered languages, Android 14 introduces the Grammatical Inflection API, which lets you add support for grammatical gender without refactoring your app.

Preferenze regionali

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.

Accessibilità

Ridimensionamento non lineare dei caratteri al 200%

Starting in Android 14, the system supports font scaling up to 200%, providing low-vision users with additional accessibility options that align with Web Content Accessibility Guidelines (WCAG).

To prevent large text elements on screen from scaling too large, the system applies a nonlinear scaling curve. This scaling strategy means that large text doesn't scale at the same rate as smaller text. Nonlinear font scaling helps preserve the proportional hierarchy between elements of different sizes while mitigating issues with linear text scaling at high degrees (such as text being cut off or text that becomes harder to read due to an extremely large display sizes).

Test your app with nonlinear font scaling

Enable the maximum font size in a device's accessibility settings to test your app.

If you already use scaled pixels (sp) units to define text sizing, then these additional options and scaling improvements are applied automatically to the text in your app. However, you should still perform UI testing with the maximum font size enabled (200%) to ensure that your app applies the font sizes correctly and can accommodate larger font sizes without impacting usability.

To enable 200% font size, follow these steps:

  1. Open the Settings app and navigate to Accessibility > Display size and text.
  2. For the Font size option, tap the plus (+) icon until the maximum font size setting is enabled, as shown in the image that accompanies this section.

Use scaled pixel (sp) units for text-sizes

Remember to always specify text sizes in sp units. When your app uses sp units, Android can apply the user's preferred text size and scale it appropriately.

Don't use sp units for padding or define view heights assuming implicit padding: with nonlinear font scaling sp dimensions might not be proportional, so 4sp + 20sp might not equal 24sp.

Convert scaled pixel (sp) units

Use TypedValue.applyDimension() to convert from sp units to pixels, and use TypedValue.deriveDimension() to convert pixels to sp. These methods apply the appropriate nonlinear scaling curve automatically.

Avoid hardcoding equations using Configuration.fontScale or DisplayMetrics.scaledDensity. Because font scaling is nonlinear, the scaledDensity field is no longer accurate. The fontScale field should be used for informational purposes only because fonts are no longer scaled with a single scalar value.

Use sp units for lineHeight

Always define android:lineHeight using sp units instead of dp, so the line height scales along with your text. Otherwise, if your text is sp but your lineHeight is in dp or px, it doesn't scale and looks cramped. TextView automatically corrects the lineHeight so that your intended proportions are preserved, but only if both textSize and lineHeight are defined in sp units.

Fotocamera e contenuti multimediali

Ultra HDR per le immagini

An illustration of Standard Dynamic Range (SDR) versus High Dynamic Range (HDR) image quality.

Android 14 adds support for High Dynamic Range (HDR) images that retain more of the information from the sensor when taking a photo, which enables vibrant colors and greater contrast. Android uses the Ultra HDR format, which is fully backward compatible with JPEG images, allowing apps to seamlessly interoperate with HDR images, displaying them in Standard Dynamic Range (SDR) as needed.

Rendering these images in the UI in HDR is done automatically by the framework when your app opts in to using HDR UI for its Activity Window, either through a manifest entry or at runtime by calling Window.setColorMode(). You can also capture compressed Ultra HDR still images on supported devices. With more colors recovered from the sensor, editing in post can be more flexible. The Gainmap associated with Ultra HDR images can be used to render them using OpenGL or Vulkan.

Zoom, messa a fuoco, Postview e altro ancora nelle estensioni della fotocamera

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:

Zoom in-sensor

When REQUEST_AVAILABLE_CAPABILITIES_STREAM_USE_CASE in CameraCharacteristics contains SCALER_AVAILABLE_STREAM_USE_CASES_CROPPED_RAW, your app can use advanced sensor capabilities to give a cropped RAW stream the same pixels as the full field of view by using a CaptureRequest with a RAW target that has stream use case set to CameraMetadata.SCALER_AVAILABLE_STREAM_USE_CASES_CROPPED_RAW. By implementing the request override controls, the updated camera gives users zoom control even before other camera controls are ready.

Audio USB senza perdita di dati

Android 14 支持无损音频格式，可通过 USB 有线耳机提供发烧友级体验。您可以查询 USB 设备的首选混音器属性，注册监听器以监听首选混音器属性的更改，以及使用 AudioMixerAttributes 类配置混音器属性。此类表示音频混音器的格式，例如声道掩码、采样率和行为。该类允许直接发送音频，而无需混音、调节音量或处理效果。

Produttività e strumenti per gli sviluppatori

Gestore delle credenziali

Android 14 adds Credential Manager as a platform API, with additional support back to Android 4.4 (API level 19) devices through a Jetpack Library using Google Play services. Credential Manager aims to make sign-in easier for users with APIs that retrieve and store credentials with user-configured credential providers. Credential Manager supports multiple sign-in methods, including username and password, passkeys, and federated sign-in solutions (such as Sign-in with Google) in a single API.

Passkeys provide many advantages. For example, passkeys are built on industry standards, can work across different operating systems and browser ecosystems, and can be used with both websites and apps.

For more information, see the Credential Manager and passkeys documentation and the blogpost about Credential Manager and passkeys.

Connessione Salute

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.

Aggiornamenti di OpenJDK 17

Android 14 continues the work of refreshing Android's core libraries to align with the features in the latest OpenJDK LTS releases, including both library updates and Java 17 language support for app and platform developers.

The following features and improvements are included:

  • Updated approximately 300 java.base classes to Java 17 support.
  • Text Blocks, which introduce multi-line string literals to the Java programming language.
  • Pattern Matching for instanceof, which allows an object to be treated as having a specific type in an instanceof without any additional variables.
  • Sealed classes, which allow you restrict which classes and interfaces can extend or implement them.

Thanks to Google Play system updates (Project Mainline), over 600 million devices are enabled to receive the latest Android Runtime (ART) updates that include these changes. This is part of our commitment to give apps a more consistent, secure environment across devices, and to deliver new features and capabilities to users independent of platform releases.

Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.

Miglioramenti per gli store di app

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.

Bundle di metadati delle app

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.

Rilevare quando gli utenti acquisiscono screenshot del dispositivo

To create a more standardized experience for detecting screenshots, Android 14 introduces a privacy-preserving screenshot detection API. This API lets apps register callbacks on a per-activity basis. These callbacks are invoked, and the user is notified, when the user takes a screenshot while that activity is visible.

Esperienza utente

Azioni personalizzate della scheda di condivisione e ranking migliorato

Android 14 更新了系统 Sharesheet，以便为用户提供自定义应用操作和信息更丰富的预览结果。

添加自定义操作

对于 Android 14，您的应用可以向其调用的系统 Sharesheet 添加自定义操作。

分享表格中自定义操作的屏幕截图。

提高直接共享目标的排名

Android 14 根据来自应用的更多信号来确定直接共享目标的排名，以便为用户提供更实用的结果。为了提供最实用的排名信号，请遵循提高直接共享目标排名的准则。通讯应用还可以报告出站和入站消息的快捷方式使用情况。

共享表单中的“直接分享”行，如 1
所示

Supporto di animazioni integrate e personalizzate per il gesto Indietro predittivo

Video: Animazioni di Gesto indietro predittivo

Android 13 ha introdotto l'animazione di ritorno alla schermata Home predittiva come opzione per gli sviluppatori. Se viene utilizzato in un'app supportata con l'opzione per gli sviluppatori attivata, lo scorrimento indietro mostra un'animazione che indica che il gesto di ritorno all'indietro fa uscire dall'app e torna alla schermata Home.

Android 14 include diversi miglioramenti e nuove indicazioni per il pulsante Indietro predittivo:

Con questa release di anteprima di Android 14, tutte le funzionalità di Indietro predittivo rimangono nascoste dietro un'opzione per sviluppatori. Consulta la guida per gli sviluppatori per eseguire la migrazione della tua app al flusso di ritorno predittivo, nonché la guida per gli sviluppatori per creare transizioni in-app personalizzate.

Sostituzioni per app dei produttori di dispositivi con schermo grande

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.

Sostituzioni per app per utente con schermo grande

按应用替换项会更改应用在大屏设备上的行为。例如，无论应用的配置如何，OVERRIDE_MIN_ASPECT_RATIO_LARGE 设备制造商替换项都会将应用宽高比设置为 16:9。

借助 Android 14 QPR1，用户可以在大屏设备上通过新的设置菜单应用按应用替换项。

Condivisione schermo dell'app

借助应用界面共享功能，用户可以在录制屏幕内容时共享应用窗口，而不是整个设备屏幕。

在应用屏幕共享模式下，状态栏、导航栏、通知和其他系统界面元素会从共享显示屏中排除。系统只会分享所选应用的内容。

应用屏幕共享功能可让用户运行多个应用，但将内容共享限制为单个应用，从而提高工作效率并保护隐私。

Risposta rapida basata su LLM in Gboard su Pixel 8 Pro

On Pixel 8 Pro devices with the December Feature Drop, developers can try out higher-quality smart replies in Gboard powered by on-device Large Language Models (LLMs) running on Google Tensor.

This feature is available as a limited preview for US English in WhatsApp, Line, and KakaoTalk. It requires using a Pixel 8 Pro device with Gboard as your keyboard.

To try it out, first enable the feature in Settings > Developer Options > AiCore Settings > Enable Aicore Persistent.

Next, open a conversation in a supported app to see LLM-powered Smart Reply in Gboard's suggestion strip in response to incoming messages.

Gboard utilizes on-device LLMs to provide higher-quality smart replies.

Grafica

I percorsi sono interrogabili e interpolabili

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:

Kotlin

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

Java

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:

Kotlin

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

Java

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:

Kotlin

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

Java

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.

Mesh personalizzate con shader vertex e fragment

Android has long supported drawing triangle meshes with custom shading, but the input mesh format has been limited to a few predefined attribute combinations. Android 14 adds support for custom meshes, which can be defined as triangles or triangle strips, and can, optionally, be indexed. These meshes are specified with custom attributes, vertex strides, varying, and vertex and fragment shaders written in AGSL.

The vertex shader defines the varyings, such as position and color, while the fragment shader can optionally define the color for the pixel, typically by using the varyings created by the vertex shader. If color is provided by the fragment shader, it is then blended with the current Paint color using the blend mode selected when drawing the mesh. Uniforms can be passed into the fragment and vertex shaders for additional flexibility.

Renderer del buffer hardware per Canvas

协助使用 Android 的 Canvas API 通过 硬件加速至 HardwareBuffer、Android 14 引入了 HardwareBufferRenderer。如果您的用例涉及通过 SurfaceControl 与系统合成器通信以实现低延迟绘制，此 API 特别有用。