功能和 API

Android 17 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 17 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）。

注意： 此页面列出了一些较为重要的新功能。如需了解详情，请参阅 Android 17 版本说明。

核心功能

Android 17 添加了以下与 Android 核心功能相关的新功能。

新的 ProfilingManager 触发器

Android 17 adds several new system triggers to ProfilingManager to help you collect in-depth data to debug performance issues.

The new triggers are:

• TRIGGER_TYPE_COLD_START: Trigger occurs during app cold start. It provides both a call stack sample and a system trace in the response.
• TRIGGER_TYPE_OOM: Trigger occurs when an app throws an OutOfMemoryError and provides a Java Heap Dump in response.
• TRIGGER_TYPE_KILL_EXCESSIVE_CPU_USAGE: Trigger occurs when an app is killed due to abnormal and excessive CPU usage and provides a snapshot of a running background system trace in response.
• TRIGGER_TYPE_ANOMALY: Detect system performance anomalies such as excessive binder calls and excessive memory usage.

To understand how to set up the system trigger, see the documentation on trigger-based profiling and how to retrieve and upload profiles and analyze profiling data.

Profiling trigger for app anomalies

Android 17 introduces an on-device anomaly detection service that monitors for resource-intensive behaviors and potential compatibility regressions. Integrated with ProfilingManager, this service allows your app to receive profiling artifacts triggered by specific system-detected events.

Use the TRIGGER_TYPE_ANOMALY trigger to detect system performance issues such as excessive binder calls and excessive memory usage. When an app breaches OS-defined memory limits, the anomaly trigger allows developers to receive app-specific heap dumps to help identify and fix memory issues. Additionally, for excessive binder spam, the anomaly trigger provides a stack sampling profile on binder transactions.

This API callback occurs prior to any system imposed enforcements. For example, it can help developers collect debug data before the app is terminated by the system for exceeding memory limits.

fun registerAnomalyTrigger(context: Context) {
    val profilingManager =
        context.getSystemService(ProfilingManager::class.java) ?: return
    val triggers = listOf(
        ProfilingTrigger.Builder(ProfilingTrigger.TRIGGER_TYPE_ANOMALY).build()
    )
    val callbackExecutor: Executor = Executors.newSingleThreadExecutor()
    val resultCallback = Consumer<ProfilingResult> { profilingResult ->
        if (profilingResult.errorCode == ProfilingResult.ERROR_NONE) {
            // Upload profile result to server for further analysis
            profilingResult.resultFilePath?.let { setupProfileUploadWorker(it) }
        }
    }
    profilingManager.registerForAllProfilingResults(
        callbackExecutor,
        resultCallback
    )
    profilingManager.addProfilingTriggers(triggers)
}

JobDebugInfo API

Android 17 introduces new JobDebugInfo APIs to help developers debug their JobScheduler jobs--why they aren't running, how long they ran for, and other aggregated information.

The first method of the expanded JobDebugInfo APIs is getPendingJobReasonStats(), which returns a map of reasons why the job was in a pending execution state and their respective cumulative pending durations. This method joins the getPendingJobReasonsHistory() and getPendingJobReasons() methods to give you insight into why a scheduled job is not running as expected, but simplifies information retrieval by making both duration and job reason available in a single method.

For example, for a specified jobId, the method might return PENDING_JOB_REASON_CONSTRAINT_CHARGING and a duration of 60000 ms, indicating the job was pending for 60000ms due to the charging constraint not being satisfied.

通过监听器支持“空闲时允许”闹钟，减少唤醒锁定

Android 17 引入了 AlarmManager.setExactAndAllowWhileIdle 的新变体，该变体接受 OnAlarmListener 而不是 PendingIntent。这种基于回调的新机制非常适合目前依赖持续唤醒锁来执行周期性任务的应用，例如维护套接字连接的即时通讯应用。

隐私权

Android 17 包含以下新功能，可更好地保护用户隐私。

加密客户端 Hello (ECH) 平台支持

Android 17 introduces platform support for Encrypted Client Hello (ECH), a significant privacy enhancement for network communications. ECH is a TLS 1.3 extension that encrypts the Server Name Indication (SNI) during the initial TLS handshake. This encryption helps protect user privacy by making it more difficult for network intermediaries to identify the specific domain an app is connecting to.

The platform now includes the necessary APIs for networking libraries to implement ECH. This includes new capabilities in DnsResolver to query for HTTPS DNS records containing ECH configurations, and new methods in Conscrypt's SSLEngines and SSLSockets to enable ECH by passing in these configurations when connecting to a domain. Developers can configure ECH preferences, such as enabling it opportunistically or mandating its use, through the new <domainEncryption> element within the Network Security Configuration file, applicable globally or on a per-domain basis.

Popular networking libraries such as HttpEngine, WebView, and OkHttp are expected to integrate these platform APIs in future updates, making it easier for apps to adopt ECH and enhance user privacy.

For more information, see the Encrypted Client Hello documentation.

Android 联系人选择工具

The Android Contact Picker is a standardized, browsable interface for users to share contacts with your app. Available on devices running Android 17 (API level 37) or higher, the picker offers a privacy-preserving alternative to the broad READ_CONTACTS permission. Instead of requesting access to the user's entire address book, your app specifies the data fields it needs, such as phone numbers or email addresses, and the user selects specific contacts to share. This grants your app read access to only the selected data, ensuring granular control while providing a consistent user experience with built-in search, profile switching, and multi-selection capabilities without having to build or maintain the UI.

For more information, see the contact picker documentation.

安全

Android 17 添加了以下新功能，以提高设备和应用的安全性。

Android 高级保护模式 (AAPM)

Android 高级保护模式为 Android 用户提供了一套强大的新安全功能，标志着在保护用户（尤其是面临较高风险的用户）免遭复杂攻击方面迈出了重要一步。AAPM 是一项选择启用功能，只需进行一项配置设置即可激活。用户可以随时启用该功能，以应用一套主观的安全保护措施。

这些核心配置包括：禁止安装未知来源的应用（旁加载）、限制 USB 数据信号传输，以及强制执行 Google Play 保护机制扫描，从而显著减小设备的攻击面。 开发者可以使用 AdvancedProtectionManager API 与此功能集成，以检测模式的状态，从而使应用能够在用户选择启用此模式时自动采用强化型安全姿态或限制高风险功能。

PQC APK 签名

Android 现在支持混合 APK 签名方案，可保护应用的签名身份免受利用量子计算的潜在攻击威胁。此功能引入了一种新的 APK 签名方案，可让您将传统签名密钥（例如 RSA 或 EC）与新的后量子加密 (PQC) 算法 (ML-DSA) 搭配使用。

这种混合方法可确保您的应用在未来免受量子攻击，同时与依赖经典签名验证的旧版 Android 和设备保持完全向后兼容。

注意： 您需要创建一个新的经典签名密钥，以便与 PQC 密钥配对。您无法重复使用混合签名之前的经典签名密钥。

对开发者的影响

• 使用 Play 应用签名的应用：如果您使用 Play 应用签名，则可以等待 Google Play 为您提供使用 Google Play 生成的 PQC 密钥升级混合签名的选项，从而确保您的应用受到保护，而无需手动管理密钥。
• 使用自行管理密钥的应用：自行管理签名密钥的开发者可以利用更新后的 Android 构建工具（例如 apksigner）轮替到混合身份，将 PQC 密钥与新的经典密钥相结合。（您必须创建新的传统密钥，不能重复使用旧密钥。）

连接

Android 17 添加了以下功能，以改进设备和应用连接。

受限卫星网络

Implements optimizations to enable apps to function effectively over low-bandwidth satellite networks.

Note: This feature went live with the Android 16 QPR2 quarterly release. For more information, see Develop for constrained satellite networks.

用户体验和系统界面

Android 17 包含以下旨在提升用户体验的变更。

专用 Google 助理音量流

Android 17 introduces a dedicated Assistant volume stream for Assistant apps, for playback with USAGE_ASSISTANT. This change decouples Assistant audio from the standard media stream, providing users with isolated control over both volumes. This enables scenarios such as muting media playback while maintaining audibility for Assistant responses, and the other way around.

Assistant apps with access to the new MODE_ASSISTANT_CONVERSATION audio mode can further improve the volume control consistency. Assistant apps can use this mode to provide a hint to the system about an active Assistant session, ensuring the Assistant stream can be controlled outside of the active USAGE_ASSISTANT playback or with connected Bluetooth peripherals.

Handoff

Handoff is a new feature and API coming to Android 17 that app developers can integrate with to provide cross-device continuity for their users. It allows the user to start an app activity on one Android device and transition it to another Android device. Handoff runs in the background of a user's device and surfaces available activities from the user's other nearby devices through various entry points, like the launcher and taskbar, on the receiving device.

Apps can designate Handoff to launch the same native Android app, if it is installed and available on the receiving device. In this app-to-app flow, the user is deep-linked to the designated activity. Alternatively, app-to-web Handoff can be offered as a fallback option or directly implemented with URL Handoff.

Handoff support is implemented on a per-activity basis. To enable Handoff, call the setHandoffEnabled() method for the activity. Additional data may need to be passed along with the handoff so the recreated activity on the receiving device can restore appropriate state. Implement the onHandoffActivityDataRequested() callback to return a HandoffActivityData object which contains details that specify how Handoff should handle and recreate the activity on the receiving device.

实时动态 - 语义颜色 API

With Android 17, Live Update launches the Semantic Coloring APIs to support colors with universal meaning.

The following classes support semantic coloring:

• Notification
• Notification.Metric
• Notification.ProgressStyle.Point
• Notification.ProgressStyle.Segment

Coloring

• Green: Associated with safety. This color should be used for the case where it lets people know you are in the safe situation.
• Orange: For designating caution and marking physical hazards. This color should be used in the situation where users need to pay attention to set better protection setting.
• Red: Generally indicates danger, stop. It should be presented for the case where need people's attention urgently.
• Blue: Neutral color for content that is informational and should stand out from other content.

The following example shows how to apply semantic styles to text in a notification:

  val ssb = SpannableStringBuilder()
        .append("Colors: ")
        .append("NONE", Notification.createSemanticStyleAnnotation(SEMANTIC_STYLE_UNSPECIFIED), 0)
        .append(", ")
        .append("INFO", Notification.createSemanticStyleAnnotation(SEMANTIC_STYLE_INFO), 0)
        .append(", ")
        .append("SAFE", Notification.createSemanticStyleAnnotation(SEMANTIC_STYLE_SAFE), 0)
        .append(", ")
        .append("CAUTION", Notification.createSemanticStyleAnnotation(SEMANTIC_STYLE_CAUTION), 0)
        .append(", ")
        .append("DANGER", Notification.createSemanticStyleAnnotation(SEMANTIC_STYLE_DANGER), 0)

    Notification.Builder(context, channelId)
          .setSmallIcon(R.drawable.ic_icon)
          .setContentTitle("Hello World!")
          .setContentText(ssb)
          .setOngoing(true)
              .setRequestPromotedOngoing(true)

适用于 Android 17 的 UWB Downlink-TDoA API

Downlink Time Difference of Arrival (DL-TDoA) ranging lets a device determine its position relative to multiple UWB anchors by measuring the relative arrival times of signals.

Note: To use DL-TDoA ranging, the calling app must request and be granted Manifest.permission.ACCESS_FINE_LOCATION, and Manifest.permission.ACCESS_BACKGROUND_LOCATION if ranging is required while the app is in the background. For more information, see Request location permissions.

For more information and code samples, see UWB Downlink-TDoA API.