功能和 API

Android 17 面向开发者引入了一些出色的新功能和 API。以下各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:

核心功能

Android 17 添加了以下与核心 Android 功能相关的新功能。

新的 ProfilingManager 触发器

Android 17 向 ProfilingManager 添加了多个新的系统触发器,可帮助您收集深入的数据来调试性能问题。

新增的触发条件包括:

如需了解如何设置系统触发器,请参阅有关基于触发器的分析以及如何检索和分析分析数据的文档

应用异常的分析触发器

Android 17 引入了一项设备端异常检测服务,用于监控资源密集型行为和潜在的兼容性回归。此服务与 ProfilingManager 集成,可让您的应用接收由特定系统检测到的事件触发的分析工件。

使用 TRIGGER_TYPE_ANOMALY 触发器可检测系统性能问题,例如过多的 binder 调用和过多的内存用量。当应用超出操作系统定义的内存限制时,异常触发器可让开发者接收特定于应用的堆转储,以帮助他们识别和修复内存问题。此外,对于过多的 Binder 垃圾信息,异常触发器会在 Binder 事务上提供堆栈采样配置文件。

此 API 回调发生在任何系统强制执行之前。例如,它可以帮助开发者在应用因超出内存限制而被系统终止之前收集调试数据。

val profilingManager =
    applicationContext.getSystemService(ProfilingManager::class.java)
val triggers = ArrayList<ProfilingTrigger>()
triggers.add(ProfilingTrigger.Builder(ProfilingTrigger.TRIGGER_TYPE_ANOMALY))
val mainExecutor: Executor = Executors.newSingleThreadExecutor()
val resultCallback = Consumer<ProfilingResult> { profilingResult ->
    if (profilingResult.errorCode != ProfilingResult.ERROR_NONE) {
        // upload profile result to server for further analysis
        setupProfileUploadWorker(profilingResult.resultFilePath)
    }
    profilingManager.registerForAllProfilingResults(mainExecutor,
                                                    resultCallback)
    profilingManager.addProfilingTriggers(triggers)
}

JobDebugInfo API

Android 17 引入了新的 JobDebugInfo API,可帮助开发者调试其 JobScheduler 作业,了解作业未运行的原因、运行时长和其他汇总信息。

扩展后的 JobDebugInfo API 的第一个方法是 getPendingJobReasonStats(),该方法会返回一个映射,其中包含作业处于待执行状态的原因及其各自的累计待执行时长。此方法将 getPendingJobReasonsHistory()getPendingJobReasons() 方法联接在一起,可让您了解预定作业未按预期运行的原因,但通过在单个方法中同时提供时长和作业原因,简化了信息检索。

例如,对于指定的 jobId,该方法可能会返回 PENDING_JOB_REASON_CONSTRAINT_CHARGING 和 60000 毫秒的时长,表示作业因未满足充电约束而处于等待状态 60000 毫秒。

通过为“允许在空闲时运行”闹钟提供监听器支持,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于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,可提升用户隐私保护。

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 联系人选择器

Android 联系人选择工具是一个标准化的可浏览界面,用户可通过该界面与您的应用分享联系人。该选择工具适用于搭载 Android 17(API 级别 37)或更高版本的设备,可提供一种注重隐私保护的替代方案,以取代范围广泛的 READ_CONTACTS 权限。您的应用无需请求访问用户的整个地址簿,而是指定所需的数据字段(例如电话号码或电子邮件地址),然后用户选择要分享的特定联系人。这只会授予您的应用对所选数据的读取权限,从而确保精细控制,同时提供一致的用户体验,并具有内置的搜索、个人资料切换和多选功能,而无需构建或维护界面。

如需了解详情,请参阅联系人选择器文档

安全

Android 17 新增了以下功能,以提升设备和应用安全性。

Android 高级保护模式 (AAPM)

Android Advanced Protection Mode offers Android users a powerful new set of security features, marking a significant step in safeguarding users—particularly those at higher risk—from sophisticated attacks. Designed as an opt-in feature, AAPM is activated with a single configuration setting that users can turn on at any time to apply an opinionated set of security protections.

These core configurations include blocking app installation from unknown sources (sideloading), restricting USB data signaling, and mandating Google Play Protect scanning, which significantly reduces the device's attack surface area. Developers can integrate with this feature using the AdvancedProtectionManager API to detect the mode's status, enabling applications to automatically adopt a hardened security posture or restrict high-risk functionality when a user has opted in.

PQC APK 签名

Android 现在支持混合 APK 签名方案,以保护应用的签名身份免受利用量子计算的攻击的潜在威胁。此功能引入了一种新的 APK 签名方案,可让您将经典签名密钥(例如 RSA 或 EC)与新的后量子加密 (PQC) 算法 (ML-DSA) 配对。

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 和设备保持完全的向后兼容性。

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,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。
  • 使用自行管理的密钥的应用:自行管理签名密钥的开发者可以利用更新后的 Android build 工具(例如 apksigner)轮换到混合身份,将 PQC 密钥与新的经典密钥相结合。(您必须创建新的经典密钥,无法重复使用旧密钥。)

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.

用户体验和系统界面

Android 17 包含以下变更,旨在提升用户体验。

专用 Google 助理音量音频流

Android 17 针对 Google 助理应用引入了专用的 Google 助理音量串流,以便使用 USAGE_ASSISTANT 进行播放。此项变更将 Google 助理音频与标准媒体音频流分离,让用户能够单独控制这两个音频流的音量。这样一来,您就可以实现以下场景:在将媒体播放静音的同时,保持 Google 助理回答的可听性;反之亦然。

有权访问新的 MODE_ASSISTANT_CONVERSATION 音频模式的助理应用可以进一步提高音量控制的一致性。助理应用可以使用此模式向系统提供有关有效助理会话的提示,确保可以在有效 USAGE_ASSISTANT 播放之外或通过连接的蓝牙外围设备控制助理流。

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.

实时更新 - 语义颜色 API

在 Android 17 中,实时更新推出了语义着色 API,以支持具有普遍含义的颜色。

以下类支持语义着色:

填色游戏

  • 绿色:与安全相关。 此颜色应在以下情况下使用:让别人知道您处于安全状态。
  • 橙色:用于表示警告和标记物理危险。在用户需要注意以设置更好的保护设置的情况下,应使用此颜色。
  • 红色:通常表示危险、停止。它应在需要人们紧急关注的情况下呈现。
  • 蓝色:中性颜色,适用于信息性内容,应与其他内容区分开来。

以下示例展示了如何将语义样式应用于通知中的文本:

  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 下行链路 TDoA API

下行链路到达时间差 (DL-TDoA) 测距技术可让设备通过测量信号的相对到达时间来确定其相对于多个锚点的位置。

以下代码段演示了如何初始化 Ranging Manager、验证设备功能并启动 DL-TDoA 会话:

Kotlin

class RangingApp {

    fun initDlTdoa(context: Context) {
        // Initialize the Ranging Manager
        val rangingManager = context.getSystemService(RangingManager::class.java)

        // Register for device capabilities
        val capabilitiesCallback = object : RangingManager.RangingCapabilitiesCallback {
            override fun onRangingCapabilities(capabilities: RangingCapabilities) {
                // Make sure Dl-TDoA is supported before starting the session
                if (capabilities.uwbCapabilities != null && capabilities.uwbCapabilities!!.isDlTdoaSupported) {
                    startDlTDoASession(context)
                }
            }
        }
        rangingManager.registerCapabilitiesCallback(Executors.newSingleThreadExecutor(), capabilitiesCallback)
    }

    fun startDlTDoASession(context: Context) {

        // Initialize the Ranging Manager
        val rangingManager = context.getSystemService(RangingManager::class.java)

        // Create session and configure parameters
        val executor = Executors.newSingleThreadExecutor()
        val rangingSession = rangingManager.createRangingSession(executor, RangingSessionCallback())
        val rangingRoundIndexes = byteArrayOf(0)
        val config: ByteArray = byteArrayOf() // OOB config data
        val params = DlTdoaRangingParams.createFromFiraConfigPacket(config, rangingRoundIndexes)

        val rangingDevice = RangingDevice.Builder().build()
        val rawTagDevice = RawRangingDevice.Builder()
            .setRangingDevice(rangingDevice)
            .setDlTdoaRangingParams(params)
            .build()

        val dtTagConfig = RawDtTagRangingConfig.Builder(rawTagDevice).build()

        val preference = RangingPreference.Builder(DEVICE_ROLE_DT_TAG, dtTagConfig)
            .setSessionConfig(SessionConfig.Builder().build())
            .build()

        // Start the ranging session
        rangingSession.start(preference)
    }
}

private class RangingSessionCallback : RangingSession.Callback {
    override fun onDlTdoaResults(peer: RangingDevice, measurement: DlTdoaMeasurement) {
        // Process measurement results here
    }
}

Java

public class RangingApp {

    public void initDlTdoa(Context context) {

        // Initialize the Ranging Manager
        RangingManager rangingManager = context.getSystemService(RangingManager.class);

        // Register for device capabilities
        RangingManager.CapabilitiesCallback capabilitiesCallback = new RangingManager.RangingCapabilitiesCallback() {
            @Override
            public void onRangingCapabilities(RangingCapabilities capabilities) {
                // Make sure Dl-TDoA is supported before starting the session
                if (capabilities.getUwbCapabilities() != null && capabilities.getUwbCapabilities().isDlTdoaSupported()) {
                    startDlTDoASession(context);
                }
            }
        };
        rangingManager.registerCapabilitiesCallback(Executors.newSingleThreadExecutor(), capabilitiesCallback);
    }

    public void startDlTDoASession(Context context) {
        RangingManager rangingManager = context.getSystemService(RangingManager.class);

        // Create session and configure parameters
        Executor executor = Executors.newSingleThreadExecutor();
        RangingSession rangingSession = rangingManager.createRangingSession(executor, new RangingSessionCallback());
        byte[] rangingRoundIndexes = new byte[] {0};
        byte[] config = new byte[0]; // OOB config data
        DlTdoaRangingParams params = DlTdoaRangingParams.createFromFiraConfigPacket(config, rangingRoundIndexes);

        RangingDevice rangingDevice = new RangingDevice.Builder().build();
        RawRangingDevice rawTagDevice = new RawRangingDevice.Builder()
                .setRangingDevice(rangingDevice)
                .setDlTdoaRangingParams(params)
                .build();

        RawDtTagRangingConfig dtTagConfig = new RawDtTagRangingConfig.Builder(rawTagDevice).build();

        RangingPreference preference = new RangingPreference.Builder(DEVICE_ROLE_DT_TAG, dtTagConfig)
                .setSessionConfig(new SessionConfig.Builder().build())
                .build();

        // Start the ranging session
        rangingSession.start(preference);
    }

    private static class RangingSessionCallback implements RangingSession.Callback {

        @Override
        public void onDlTdoaResults(RangingDevice peer, DlTdoaMeasurement measurement) {
            // Process measurement results here
        }
    }
}

带外 (OOB) 配置

以下代码段提供了 Wi-Fi 和 BLE 的 DL-TDoA OOB 配置数据示例:

Java

// Wifi Configuration
byte[] wifiConfig = {
    (byte) 0xDD, (byte) 0x2D, (byte) 0x5A, (byte) 0x18, (byte) 0xFF, // Header
    (byte) 0x5F, (byte) 0x19, // FiRa Sub-Element
    (byte) 0x02, (byte) 0x00, // Profile ID
    (byte) 0x06, (byte) 0x02, (byte) 0x20, (byte) 0x08, // MAC Address
    (byte) 0x14, (byte) 0x01, (byte) 0x0C, // Preamble Index
    (byte) 0x27, (byte) 0x02, (byte) 0x08, (byte) 0x07, // Vendor ID
    (byte) 0x28, (byte) 0x06, (byte) 0xCA, (byte) 0xC8, (byte) 0xA6, (byte) 0xF7, (byte) 0x6F, (byte) 0x08, // Static STS IV
    (byte) 0x08, (byte) 0x02, (byte) 0x60, (byte) 0x09, // Slot Duration
    (byte) 0x1B, (byte) 0x01, (byte) 0x0A, // Slots per RR
    (byte) 0x09, (byte) 0x04, (byte) 0xE8, (byte) 0x03, (byte) 0x00, (byte) 0x00, // Duration
    (byte) 0x9F, (byte) 0x04, (byte) 0x67, (byte) 0x45, (byte) 0x23, (byte) 0x01  // Session ID
};

// BLE Configuration
byte[] bleConfig = {
    (byte) 0x2D, (byte) 0x16, (byte) 0xF4, (byte) 0xFF, // Header
    (byte) 0x5F, (byte) 0x19, // FiRa Sub-Element
    (byte) 0x02, (byte) 0x00, // Profile ID
    (byte) 0x06, (byte) 0x02, (byte) 0x20, (byte) 0x08, // MAC Address
    (byte) 0x14, (byte) 0x01, (byte) 0x0C, // Preamble Index
    (byte) 0x27, (byte) 0x02, (byte) 0x08, (byte) 0x07, // Vendor ID
    (byte) 0x28, (byte) 0x06, (byte) 0xCA, (byte) 0xC8, (byte) 0xA6, (byte) 0xF7, (byte) 0x6F, (byte) 0x08, // Static STS IV
    (byte) 0x08, (byte) 0x02, (byte) 0x60, (byte) 0x09, // Slot Duration
    (byte) 0x1B, (byte) 0x01, (byte) 0x0A, // Slots per RR
    (byte) 0x09, (byte) 0x04, (byte) 0xE8, (byte) 0x03, (byte) 0x00, (byte) 0x00, // Duration
    (byte) 0x9F, (byte) 0x04, (byte) 0x67, (byte) 0x45, (byte) 0x23, (byte) 0x01  // Session ID
};

如果您无法使用 OOB 配置(因为该配置缺失),或者需要更改不在 OOB 配置中的默认值,则可以使用 DlTdoaRangingParams.Builder 构建参数,如以下代码段所示。您可以使用以下参数代替 DlTdoaRangingParams.createFromFiraConfigPacket()

Kotlin

val dlTdoaParams = DlTdoaRangingParams.Builder(1)
    .setComplexChannel(UwbComplexChannel.Builder()
            .setChannel(9).setPreambleIndex(10).build())
    .setDeviceAddress(deviceAddress)
    .setSessionKeyInfo(byteArrayOf(0x01, 0x02, 0x03, 0x04))
    .setRangingIntervalMillis(240)
    .setSlotDuration(UwbRangingParams.DURATION_2_MS)
    .setSlotsPerRangingRound(20)
    .setRangingRoundIndexes(byteArrayOf(0x01, 0x05))
    .build()

Java

DlTdoaRangingParams dlTdoaParams = new DlTdoaRangingParams.Builder(1)
    .setComplexChannel(new UwbComplexChannel.Builder()
            .setChannel(9).setPreambleIndex(10).build())
    .setDeviceAddress(deviceAddress)
    .setSessionKeyInfo(new byte[]{0x01, 0x02, 0x03, 0x04})
    .setRangingIntervalMillis(240)
    .setSlotDuration(UwbRangingParams.DURATION_2_MS)
    .setSlotsPerRangingRound(20)
    .setRangingRoundIndexes(new byte[]{0x01, 0x05})
    .build();