功能和 API

Android 16 面向开发者引入了一些出色的新功能和 API。以下部分总结了这些功能，可帮助您开始使用相关 API。

有关新增、修改和移除的 API 的详细列表，请参阅 API 差异报告。如需详细了解新的 API，请访问 Android API 参考文档，新 API 会突出显示以方便查看。

您还应查看平台变更可能会在哪些方面影响您的应用。如需了解详情，请参阅以下页面：

• 影响以 Android 16 为目标平台的应用的行为变更
• 影响所有应用的行为变更（无论 targetSdkVersion 为何）。

核心功能

Android 包含可扩展 Android 系统核心功能的新 API。

2025 年将发布两个 Android API 版本

• 此预览版适用于 Android 的下一个主要版本，计划于 2025 年第 2 季度发布。此版本与我们过去的所有 API 版本类似，我们可以进行计划性的行为更改，这些更改通常与 targetSdkVersion 相关联。
• 我们计划提前一个季度（2021 年第 2 季度，而非之前的第 3 季度）发布主要版本，以便更好地与整个生态系统中的设备发布时间表保持一致，让更多设备能够更早地搭载 Android 主要版本。由于主要版本将于第 2 季度发布，因此您需要比往年提前几个月进行年度兼容性测试，以确保您的应用已做好准备。
• 我们计划在 2025 年第 4 季度再发布一次，届时还将推出新的开发者 API。2025 年只有第二季度的主要版本包含可能影响应用的计划行为变更。

除了新的开发者 API 之外，第 4 季度次要版本还将包含功能更新、优化和 bug 修复；其中不会包含任何会影响应用的行为变更。

我们将继续每季度发布 Android 版本。在 API 版本之间，第 1 季度和第 3 季度的更新将提供增量更新，以帮助确保持续提供高质量的服务。我们正积极与设备合作伙伴合作，将 Q2 版本推广到尽可能多的设备。

在主要版本和次要版本中使用新 API

目前，使用 SDK_INT 常量与 VERSION_CODES 结合使用，即可通过检查 API 级别来保护代码块。我们将继续支持主要 Android 版本。

if (SDK_INT >= VERSION_CODES.BAKLAVA) {
  // Use APIs introduced in Android 16
}

新的 SDK_INT_FULL 常量可用于针对主要版本和次要版本进行 API 检查，并使用新的 VERSION_CODES_FULL 枚举。

if (SDK_INT_FULL >= VERSION_CODES_FULL.[MAJOR or MINOR RELEASE]) {
  // Use APIs introduced in a major or minor release
}

您还可以使用 Build.getMinorSdkVersion() 方法仅获取 SDK 次要版本。

val minorSdkVersion = Build.getMinorSdkVersion(VERSION_CODES_FULL.BAKLAVA)

这些 API 尚未最终确定，可能会发生变化，因此如果您有任何疑虑，请向我们发送反馈。

注意： Google Play 中应用的目标 API 级别要求及其相关日期保持不变；我们计划每年发布一次要求，该要求将与主要 API 级别相关联。

用户体验和系统界面

Android 16 为应用开发者和用户提供了更多控制权和灵活性，以便他们根据自己的需求配置设备。

以进度为中心的通知

Android 16 引入了以进度为中心的通知，可帮助用户顺畅地跟踪用户发起的端到端历程。

Notification.ProgressStyle 是一种新的通知样式，可让您创建以进度为中心的通知。主要用例包括共享车辆、送货和导航。在 Notification.ProgressStyle 类中，您可以使用点和细分来表示用户体验历程中的状态和里程碑。

To learn more, see the Progress-centric notifications documentation page.

锁屏上显示的以进度为中心的通知。

在通知栏中显示的以进度为中心的通知。

预测性返回更新

Android 16 adds new APIs to help you enable predictive back system animations in gesture navigation such as the back-to-home animation. Registering the onBackInvokedCallback with the new PRIORITY_SYSTEM_NAVIGATION_OBSERVER allows your app to receive the regular onBackInvoked call whenever the system handles a back navigation without impacting the normal back navigation flow.

Android 16 additionally adds the finishAndRemoveTaskCallback() and moveTaskToBackCallback. By registering these callbacks with the OnBackInvokedDispatcher, the system can trigger specific behaviors and play corresponding ahead-of-time animations when the back gesture is invoked.

更丰富的触感反馈

自诞生之日起，Android 就提供了对触感反馈致动器的控制。

Android 11 添加了对更复杂的触感反馈效果的支持，更高级的致动器可以通过设备定义的语义基元 VibrationEffect.Compositions 支持这些效果。

Android 16 添加了触感反馈 API，让应用能够定义触感反馈效果的振幅和频率曲线，同时抽象出设备功能之间的差异。

开发者工作效率和工具

虽然我们为提高您的工作效率而开展的大部分工作都围绕 Android Studio、Jetpack Compose 和 Android Jetpack 库等工具展开，但我们一直在寻找各种方法来帮助您在平台上实现愿景。

动态壁纸的内容处理

在 Android 16 中，动态壁纸框架将获得一个新的 content API，以应对由用户驱动的动态壁纸带来的挑战。目前，包含用户提供的内容的实时壁纸需要复杂的服务专用实现。Android 16 引入了 WallpaperDescription 和 WallpaperInstance。借助 WallpaperDescription，您可以识别同一服务中的动态壁纸的不同实例。例如，如果某张壁纸同时在主屏幕和锁定屏幕上显示，则这两种情况下显示的内容可能各不相同。壁纸选择器和 WallpaperManager 会使用此元数据更好地向用户呈现壁纸，从而简化创建多样化个性化动态壁纸体验的过程。

性能和电池

Android 16 引入了可帮助您收集应用数据洞见的 API。

系统触发的性能分析

ProfilingManager was added in Android 15, giving apps the ability to request profiling data collection using Perfetto on public devices in the field. However, since this profiling must be started from the app, critical flows such as startups or ANRs would be difficult or impossible for apps to capture.

To help with this, Android 16 introduces system-triggered profiling to ProfilingManager. Apps can register interest in receiving traces for certain triggers such as cold start reportFullyDrawn or ANRs, and then the system starts and stops a trace on the app's behalf. After the trace completes, the results are delivered to the app's data directory.

ApplicationStartInfo 中的启动组件

ApplicationStartInfo 在 Android 15 中添加，可让应用查看进程启动原因、启动类型、启动时间、节流和其他实用诊断数据。Android 16 添加了 getStartComponent()，用于区分触发启动的组件类型，这有助于优化应用的启动流程。

更好的作业自检

The JobScheduler#getPendingJobReason() API returns a reason why a job might be pending. However, a job might be pending for multiple reasons.

In Android 16, we are introducing a new API JobScheduler#getPendingJobReasons(int jobId), which returns multiple reasons why a job is pending, due to both explicit constraints set by the developer and implicit constraints set by the system.

We're also introducing JobScheduler#getPendingJobReasonsHistory(int jobId), which returns a list of the most recent constraint changes.

We recommend using the API to help you debug why your jobs may not be executing, especially if you're seeing reduced success rates of certain tasks or have bugs around latency of certain job completion. For example, updating widgets in the background failed to occur or prefetch job failed to be called prior to app start.

This can also better help you understand if certain jobs are not completing due to system defined constraints versus explicitly set constraints.

自动调节刷新率

Android 15 中引入的自适应刷新率 (ARR) 可让受支持硬件上的显示屏刷新率使用离散的 VSync 步长来适应内容帧速率。这不仅降低了功耗，还无需进行可能导致卡顿的模式切换。

Android 16 引入了 hasArrSupport() 和 getSuggestedFrameRate(int)，同时恢复了 getSupportedRefreshRates()，以便您的应用更轻松地利用 ARR。RecyclerView 1.4 在从快速滑动或平滑滚动中稳定下来时会在内部支持 ARR，我们将继续努力，将 ARR 支持添加到更多 Jetpack 库中。这篇帧速率文章介绍了许多可用于设置帧速率的 API，以便您的应用可以直接使用 ARR。

ADPF 中的 Headroom API

The SystemHealthManager introduces the getCpuHeadroom and getGpuHeadroom APIs, designed to provide games and resource-intensive apps with estimates of available CPU and GPU resources. These methods offer a way for you to gauge how your app or game can best improve system health, particularly when used in conjunction with other Android Dynamic Performance Framework (ADPF) APIs that detect thermal throttling.

By using CpuHeadroomParams and GpuHeadroomParams on supported devices, you can customize the time window used to compute the headroom and select between average or minimum resource availability. This can help you reduce your CPU or GPU resource usage accordingly, leading to better user experiences and improved battery life.

无障碍

Android 16 添加了新的无障碍功能 API 和功能，可帮助您将应用推广到每位用户。

改进了无障碍功能 API

Android 16 adds additional APIs to enhance UI semantics that help improve consistency for users that rely on accessibility services, such as TalkBack.

Outline text for maximum text contrast

Users with low vision often have reduced contrast sensitivity, making it challenging to distinguish objects from their backgrounds. To help these users, Android 16 introduces outline text, replacing high contrast text, which draws a larger contrasting area around text to greatly improve legibility.

Android 16 contains new AccessibilityManager APIs to let your apps check or register a listener to see if this mode is enabled. This is primarily for UI Toolkits like Compose to offer a similar visual experience. If you maintain a UI Toolkit library or your app performs custom text rendering that bypasses the android.text.Layout class then you can use this to know when outline text is enabled.

Text with enhanced contrast before and after Android 16's new outline text accessibility feature

Duration added to TtsSpan

Android 16 extends TtsSpan with a TYPE_DURATION, consisting of ARG_HOURS, ARG_MINUTES, and ARG_SECONDS. This lets you directly annotate time duration, ensuring accurate and consistent text-to-speech output with services like TalkBack.

Support elements with multiple labels

Android currently allows UI elements to derive their accessibility label from another, and now offers the ability for multiple labels to be associated, a common scenario in web content. By introducing a list-based API within AccessibilityNodeInfo, Android can directly support these multi-label relationships. As part of this change, we've deprecated AccessibilityNodeInfo#setLabeledBy and #getLabeledBy in favor of #addLabeledBy, #removeLabeledBy, and #getLabeledByList.

Improved support for expandable elements

Android 16 adds accessibility APIs that allow you to convey the expanded or collapsed state of interactive elements, such as menus and expandable lists. By setting the expanded state using setExpandedState and dispatching TYPE_WINDOW_CONTENT_CHANGED AccessibilityEvents with a CONTENT_CHANGE_TYPE_EXPANDED content change type, you can ensure that screen readers like TalkBack announce state changes, providing a more intuitive and inclusive user experience.

Indeterminate ProgressBars

Android 16 adds RANGE_TYPE_INDETERMINATE, giving a way for you to expose RangeInfo for both determinate and indeterminate ProgressBar widgets, allowing services like TalkBack to more consistently provide feedback for progress indicators.

Tri-state CheckBox

The new AccessibilityNodeInfo getChecked and setChecked(int) methods in Android 16 now support a "partially checked" state in addition to "checked" and "unchecked." This replaces the deprecated boolean isChecked and setChecked(boolean).

Supplemental descriptions

When an accessibility service describes a ViewGroup, it combines content labels from its child views. If you provide a contentDescription for the ViewGroup, accessibility services assume you are also overriding the description of non-focusable child views. This can be problematic if you want to label things like a drop-down (for example, "Font Family") while preserving the current selection for accessibility (for example, "Roboto"). Android 16 adds setSupplementalDescription so you can provide text that provides information about a ViewGroup without overriding information from its children.

Required form fields

Android 16 adds setFieldRequired to AccessibilityNodeInfo so apps can tell an accessibility service that input to a form field is required. This is an important scenario for users filling out many types of forms, even things as simple as a required terms and conditions checkbox, helping users to consistently identify and quickly navigate between required fields.

使用 LEA 助听器进行语音通话时，将手机作为麦克风输入设备

Android 16 新增了一项功能，让 LE Audio 助听器用户能够在助听器的内置麦克风和手机上的麦克风之间切换，以进行语音通话。在嘈杂的环境或助听器麦克风可能无法正常工作的其他情况下，这会很有帮助。

LEA 助听器的环境音量控制

Android 16 adds the capability for users of LE Audio hearing aids to adjust the volume of ambient sound that is picked up by the hearing aid's microphones. This can be helpful in situations where background noise is too loud or too quiet.

相机

Android 16 增强了对专业相机用户的支持，允许混合自动曝光以及精确的色温和色调调整。新的夜间模式指示器可帮助您的应用了解何时切换到夜间模式相机拍摄会话以及何时切换回来。新的 Intent 操作让拍摄动态照片变得更加轻松，并且我们还在继续改进 UltraHDR 图片，增加了对 HEIC 编码的支持，并引入了 ISO 21496-1 草案标准中的新参数。

混合自动曝光

Android 16 向 Camera2 添加了新的混合自动曝光模式，让您可以手动控制曝光的特定方面，同时让自动曝光 (AE) 算法处理其余部分。您可以控制 ISO + AE 和曝光时间 + AE，与当前方法（您要么完全手动控制，要么完全依赖自动曝光）相比，可提供更大的灵活性。

fun setISOPriority() {
    // ... (Your existing code before the snippet) ...

    val availablePriorityModes = mStaticInfo.characteristics.get(
        CameraCharacteristics.CONTROL_AE_AVAILABLE_PRIORITY_MODES
    )

    // ... (Your existing code between the snippets) ...

    // Turn on AE mode to set priority mode
    reqBuilder.set(
        CaptureRequest.CONTROL_AE_MODE,
        CameraMetadata.CONTROL_AE_MODE_ON
    )
    reqBuilder.set(
        CaptureRequest.CONTROL_AE_PRIORITY_MODE,
        CameraMetadata.CONTROL_AE_PRIORITY_MODE_SENSOR_SENSITIVITY_PRIORITY
    )
    reqBuilder.set(
        CaptureRequest.SENSOR_SENSITIVITY,
        TEST_SENSITIVITY_VALUE
    )
    val request: CaptureRequest = reqBuilder.build()

    // ... (Your existing code after the snippet) ...
}

精确调整色温和色调

Android 16 adds camera support for fine color temperature and tint adjustments to better support professional video recording applications. In previous Android versions, you could control white balance settings through CONTROL_AWB_MODE, which contains options limited to a preset list, such as Incandescent, Cloudy, and Twilight. The COLOR_CORRECTION_MODE_CCT enables the use of COLOR_CORRECTION_COLOR_TEMPERATURE and COLOR_CORRECTION_COLOR_TINT for precise adjustments of white balance based on the correlated color temperature.

fun setCCT() {
    // ... (Your existing code before this point) ...

    val colorTemperatureRange: Range<Int> =
        mStaticInfo.characteristics[CameraCharacteristics.COLOR_CORRECTION_COLOR_TEMPERATURE_RANGE]

    // Set to manual mode to enable CCT mode
    reqBuilder[CaptureRequest.CONTROL_AWB_MODE] = CameraMetadata.CONTROL_AWB_MODE_OFF
    reqBuilder[CaptureRequest.COLOR_CORRECTION_MODE] = CameraMetadata.COLOR_CORRECTION_MODE_CCT
    reqBuilder[CaptureRequest.COLOR_CORRECTION_COLOR_TEMPERATURE] = 5000
    reqBuilder[CaptureRequest.COLOR_CORRECTION_COLOR_TINT] = 30

    val request: CaptureRequest = reqBuilder.build()

    // ... (Your existing code after this point) ...
}

The following examples show how a photo would look after applying different color temperature and tint adjustments:

The original image with no color temperature or tint adjustments applied.

The image with color temperature adjusted to 3000.

The image with color temperature adjusted to 7000.

The image with tint levels lowered by 50.

The image with tint levels raised by 50.

相机夜间模式场景检测

为了帮助应用了解何时切换到夜间模式相机会话以及何时从夜间模式相机会话切换出，Android 16 添加了 EXTENSION_NIGHT_MODE_INDICATOR。如果受支持，则可在 Camera2 内的 CaptureResult 中使用。

这是我们在Instagram 如何让用户拍出令人惊艳的低光照片博文中提到的即将推出的 API。该博文提供了有关如何实现夜间模式的实用指南，并附有一份案例研究，该案例研究将应用内夜间模式照片质量的提升与通过应用内相机分享的照片数量的增加联系起来。

动态照片拍摄 intent 操作

Android 16 添加了标准 intent 操作 ACTION_MOTION_PHOTO_CAPTURE 和 ACTION_MOTION_PHOTO_CAPTURE_SECURE，用于请求相机应用拍摄动态照片并将其返回。

您必须传递额外的 EXTRA_OUTPUT 来控制将图片写入的位置，或者通过 Intent.setClipData(ClipData) 传递 Uri。如果您未设置 ClipData，系统会在调用 Context.startActivity(Intent) 时将其复制到该位置。

动态照片示例，显示静态图片和动态播放画面。

UltraHDR 图片增强功能

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

Android 16 continues our work to deliver dazzling image quality with UltraHDR images. It adds support for UltraHDR images in the HEIC file format. These images will get ImageFormat type HEIC_ULTRAHDR and will contain an embedded gainmap similar to the existing UltraHDR JPEG format. We're working on AVIF support for UltraHDR as well, so stay tuned.

In addition, Android 16 implements additional parameters in UltraHDR from the ISO 21496-1 draft standard, including the ability to get and set the colorspace that gainmap math should be applied in, as well as support for HDR encoded base images with SDR gainmaps.

图形

Android 16 包含最新的图形改进，例如使用 AGSL 的自定义图形效果。

使用 AGSL 实现自定义图形效果

Android 16 添加了 RuntimeColorFilter 和 RuntimeXfermode，让您可以创作阈值、Sepia 和 Hue Saturation 等复杂效果，并将其应用于绘制调用。从 Android 13 开始，您可以使用 AGSL 创建扩展 Shader 的自定义 RuntimeShader。新 API 反映了这一点，添加了由 AGSL 驱动的 RuntimeColorFilter（用于扩展 ColorFilter）和 Xfermode 效果，让您可以在源像素和目标像素之间实现基于 AGSL 的自定义合成和混合。

private val thresholdEffectString = """
    uniform half threshold;

    half4 main(half4 c) {
        half luminosity = dot(c.rgb, half3(0.2126, 0.7152, 0.0722));
        half bw = step(threshold, luminosity);
        return bw.xxx1 * c.a;
    }"""

fun setCustomColorFilter(paint: Paint) {
   val filter = RuntimeColorFilter(thresholdEffectString)
   filter.setFloatUniform(0.5);
   paint.colorFilter = filter
}

连接

Android 16 更新了平台，让您的应用能够利用通信和无线技术方面的最新进展。

测距功能，安全性更高

Android 16 adds support for robust security features in Wi-Fi location on supported devices with Wi-Fi 6's 802.11az, allowing apps to combine the higher accuracy, greater scalability, and dynamic scheduling of the protocol with security enhancements including AES-256-based encryption and protection against MITM attacks. This allows it to be used more safely in proximity use cases, such as unlocking a laptop or a vehicle door. 802.11az is integrated with the Wi-Fi 6 standard, leveraging its infrastructure and capabilities for wider adoption and easier deployment.

通用测距 API

Android 16 includes the new RangingManager, which provides ways to determine the distance and angle on supported hardware between the local device and a remote device. RangingManager supports the usage of a variety of ranging technologies such as BLE channel sounding, BLE RSSI-based ranging, Ultra Wideband, and Wi-Fi round trip time.

配套设备管理器设备存在性

In Android 16, new APIs are being introduced for binding your companion app service. Service will be bound when BLE is in range and Bluetooth is connected and service will be unbound when BLE is out of range or Bluetooth is disconnected. App will receives a new 'onDevicePresenceEvent()' callback based on various of DevicePresenceEvent. More details can be found in 'startObservingDevicePresence(ObservingDevicePresenceRequest)'.

媒体

Android 16 包含各种可提升媒体体验的功能。

改进了照片选择器

照片选择器为用户提供了一种安全的内置授权方式，让用户可以向应用授予对本地存储空间和云端存储空间中所选图片和视频的访问权限，而不是对整个媒体库的访问权限。通过 Google 系统更新和 Google Play 服务组合使用模块化系统组件，该工具向后支持到 Android 4.4（API 级别 19）。只需几行代码即可与相关的 Android Jetpack 库集成。

Android 16 对照片选择器进行了以下改进：

• 嵌入式照片选择器：新 API，可让应用将照片选择器嵌入其视图层次结构中。这样，它就感觉像是应用中更为集成的一部分，同时仍可利用进程隔离功能，让用户能够选择媒体，而无需应用拥有过于宽泛的权限。为了最大限度地提高跨平台版本的兼容性并简化集成，如果您想集成嵌入式照片选择器，则需要使用即将推出的 Android Jetpack 库。
• 照片选择器中的云搜索：新的 API 可让 Android 照片选择器从云端媒体提供商中进行搜索。照片选择器中的搜索功能即将推出。

高级专业视频

Android 16 引入了对高级专业视频 (APV) 编解码器的支持，该编解码器专为专业级高品质视频录制和后期制作而设计。

APV 编解码器标准具有以下特点：

• 感知上无损的视频画质（接近原始视频画质）
• 复杂度低且吞吐量高的仅帧内编码（无像素域预测），以更好地支持编辑工作流
• 支持高比特率范围（最高几十 Gbps），适用于 2K、4K 和 8K 分辨率内容，由轻量级熵编码方案实现
• 帧平铺，用于沉浸式内容和启用并行编码和解码
• 支持各种色度采样格式和位深
• 支持多次解码和重新编码，且不会严重降低视觉质量
• 支持多视图视频和辅助视频，例如深度、Alpha 和预览
• 支持 HDR10/10+ 和用户定义的元数据

OpenAPV 项目提供了 APV 的参考实现。Android 16 将实现对 APV 422-10 配置文件的支持，该配置文件提供 YUV 422 色彩采样以及 10 位编码，并且目标比特率最高可达 2 Gbps。

隐私权

Android 16 包含各种可帮助应用开发者保护用户隐私的功能。

“健康数据共享”更新

Health Connect 添加了 ACTIVITY_INTENSITY，这是一种根据世界卫生组织关于中等强度和剧烈强度活动的指南定义的数据类型。每个记录都需要提供开始时间、结束时间以及活动强度（中等或剧烈）。

Health Connect 还包含支持医疗记录的更新版 API。这样一来，应用便可在征得用户明确同意的情况下，读取和写入 FHIR 格式的医疗记录。

Privacy Sandbox on Android

Android 16 incorporates the latest version of the Privacy Sandbox on Android, part of our ongoing work to develop technologies where users know their privacy is protected. Our website has more about the Privacy Sandbox on Android developer beta program to help you get started. Check out the SDK Runtime which allows SDKs to run in a dedicated runtime environment separate from the app they are serving, providing stronger safeguards around user data collection and sharing.

安全

Android 16 包含可帮助您增强应用安全性和保护应用数据的功能。

密钥共享 API

Android 16 adds APIs that support sharing access to Android Keystore keys with other apps. The new KeyStoreManager class supports granting and revoking access to keys by app uid, and includes an API for apps to access shared keys.

设备规格

Android 16 为您的应用提供支持，让其能够充分利用 Android 的各种设备规格。

电视画质和音质标准化框架

The new MediaQuality package in Android 16 exposes a set of standardized APIs for access to audio and picture profiles and hardware-related settings. This allows streaming apps to query profiles and apply them to media dynamically:

• Movies mastered with a wider dynamic range require greater color accuracy to see subtle details in shadows and adjust to ambient light, so a profile that prefers color accuracy over brightness may be appropriate.
• Live sporting events are often mastered with a narrow dynamic range, but are often watched in daylight, so a profile that preferences brightness over color accuracy can give better results.
• Fully interactive content wants minimal processing to reduce latency, and wants higher frame rates, which is why many TV's ship with a game profile.

The API allows apps to switch between profiles and users to enjoy tuning supported TVs to best suit their content.

国际化

Android 16 添加了多项功能，可在用户使用不同语言时提升用户体验。

竖排文字

Android 16 adds low-level support for rendering and measuring text vertically to provide foundational vertical writing support for library developers. This is particularly useful for languages like Japanese that commonly use vertical writing systems. A new flag, VERTICAL_TEXT_FLAG, has been added to the Paint class. When this flag is set using Paint.setFlags, Paint's text measurement APIs will report vertical advances instead of horizontal advances, and Canvas will draw text vertically.

Note: Current high-level text APIs, such as Text in Jetpack Compose, TextView, Layout classes and their subclasses don't support vertical writing systems, and don't support using the VERTICAL_TEXT_FLAG.

val text = "「春は、曙。」"
Box(
    Modifier.padding(innerPadding).background(Color.White).fillMaxSize().drawWithContent {
        drawIntoCanvas { canvas ->
            val paint = Paint().apply { textSize = 64.sp.toPx() }
            // Draw text vertically
            paint.flags = paint.flags or VERTICAL_TEXT_FLAG
            val height = paint.measureText(text)
            canvas.nativeCanvas.drawText(
                text,
                0,
                text.length,
                size.width / 2,
                (size.height - height) / 2,
                paint
            )
        }
    }
) {}

度量制自定义

Users can now customize their measurement system in regional preferences within Settings. The user preference is included as part of the locale code, so you can register a BroadcastReceiver on ACTION_LOCALE_CHANGED to handle locale configuration changes when regional preferences change.

Using formatters can help match the local experience. For example, "0.5 in" in English (United States), is "12,7 mm" for a user who has set their phone to English (Denmark) or who uses their phone in English (United States) with the metric system as the measurement system preference.

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