鸿蒙跨端低功耗蓝牙音箱系统开发指南原创

进修的泡芙

发布于 2025-6-23 13:12

浏览

0收藏

鸿蒙跨端低功耗蓝牙音箱系统开发指南

一、项目概述

本文基于HarmonyOS的蓝牙音频和硬件加速能力，开发一套低功耗蓝牙音箱系统。该系统整合音频解码硬件加速、蓝牙连接参数动态调整和休眠模式快速恢复技术，并借鉴《鸿蒙跨端U同步》中的多设备同步技术，实现高效音频传输、多设备协同播放和智能功耗管理。

二、系统架构

±--------------------+ ±--------------------+ ±--------------------+
控制设备 <-----> 分布式数据总线 <-----> 蓝牙音箱
(手机/平板) (Distributed Bus) (多设备组)
±---------±---------+ ±---------±---------+ ±---------±---------+

±---------v----------+ ±---------v----------+ ±---------v----------+
音频控制模块连接管理模块音频处理模块
(播放/同步) (参数优化/休眠) (解码/硬件加速)

±--------------------+ ±--------------------+ ±--------------------+

三、核心代码实现
蓝牙音频服务实现

// src/main/ets/service/BluetoothAudioService.ts
import { distributedData } from ‘@ohos.data.distributedData’;
import { BusinessError } from ‘@ohos.base’;
import { bluetooth } from ‘@ohos.bluetooth’;
import { audio } from ‘@ohos.multimedia.audio’;
import { power } from ‘@ohos.power’;
import { taskpool } from ‘@ohos.taskpool’;
import { fileIo } from ‘@ohos.fileio’;
import { zlib } from ‘@ohos.zlib’;

interface AudioDevice {
deviceId: string;
name: string;
address: string;
isConnected: boolean;
batteryLevel: number;
isSynced: boolean;
interface PlaybackState {

currentPosition: number; // 当前播放位置(ms)
duration: number; // 总时长(ms)
status: ‘playing’ ‘paused’
‘stopped’;
volume: number; // 音量 0-100
isSynced: boolean;
interface ConnectionParams {

interval: number; // 连接间隔(ms)
latency: number; // 从设备延迟
timeout: number; // 超时时间(ms)
mtu: number; // MTU大小
isSynced: boolean;
export class BluetoothAudioService {

private static instance: BluetoothAudioService;
private kvStore: distributedData.KVStore | null = null;
private readonly STORE_ID = ‘bt_audio_store’;
private audioRenderer: audio.AudioRenderer | null = null;
private bluetoothA2dp: bluetooth.A2dpProfile | null = null;
private connectedDevices: AudioDevice[] = [];
private playbackState: PlaybackState = {
currentPosition: 0,
duration: 0,
status: ‘stopped’,
volume: 80,
isSynced: false
};
private connectionParams: ConnectionParams = {
interval: 30,
latency: 0,
timeout: 3000,
mtu: 512,
isSynced: false
};
private lastSyncTime: number = 0;
private readonly SYNC_INTERVAL = 5 60 1000; // 5分钟同步一次

private constructor() {
this.initKVStore();
this.loadLocalData();
this.initBluetooth();
public static getInstance(): BluetoothAudioService {

if (!BluetoothAudioService.instance) {
  BluetoothAudioService.instance = new BluetoothAudioService();

return BluetoothAudioService.instance;

private async initKVStore(): Promise<void> {

try {
  const options: distributedData.KVManagerConfig = {
    bundleName: 'com.example.btaudio',
    userInfo: {
      userId: '0',
      userType: distributedData.UserType.SAME_USER_ID

};

  const kvManager = distributedData.createKVManager(options);
  this.kvStore = await kvManager.getKVStore({
    storeId: this.STORE_ID,
    options: {
      createIfMissing: true,
      encrypt: false,
      backup: false,
      autoSync: true,
      kvStoreType: distributedData.KVStoreType.SINGLE_VERSION

});

  this.kvStore.on('dataChange', distributedData.SubscribeType.SUBSCRIBE_TYPE_REMOTE, (data) => {
    this.handleRemoteDataChange(data);
  });

catch (e) {

  console.error(Failed to initialize KVStore. Code: {e.code}, message: {e.message});

}

private async loadLocalData(): Promise<void> {
try {
// 加载设备列表
const deviceFile = await fileIo.open(‘data/audio_devices.bin’, 0o666);
const deviceData = await fileIo.read(deviceFile.fd, new ArrayBuffer(0));
await fileIo.close(deviceFile.fd);

  if (deviceData) {
    const decompressed = await zlib.deflateSync(deviceData);
    this.connectedDevices = JSON.parse(String.fromCharCode.apply(null, new Uint8Array(decompressed)));

// 加载播放状态

  const stateFile = await fileIo.open('data/playback_state.bin', 0o666);
  const stateData = await fileIo.read(stateFile.fd, new ArrayBuffer(0));
  await fileIo.close(stateFile.fd);
  
  if (stateData) {
    const decompressed = await zlib.deflateSync(stateData);
    this.playbackState = JSON.parse(String.fromCharCode.apply(null, new Uint8Array(decompressed)));

// 加载连接参数

  const paramFile = await fileIo.open('data/connection_params.bin', 0o666);
  const paramData = await fileIo.read(paramFile.fd, new ArrayBuffer(0));
  await fileIo.close(paramFile.fd);
  
  if (paramData) {
    const decompressed = await zlib.deflateSync(paramData);
    this.connectionParams = JSON.parse(String.fromCharCode.apply(null, new Uint8Array(decompressed)));

} catch (e) {

  console.log('No local data found or error reading file');

}

private async saveLocalData(): Promise<void> {
try {
// 确保目录存在
await fileIo.mkdir(‘data’);

  // 保存设备列表
  const deviceStr = JSON.stringify(this.connectedDevices);
  const deviceCompressed = await zlib.inflateSync(new Uint8Array(deviceStr.split('').map(c => c.charCodeAt(0))));
  
  const deviceFile = await fileIo.open('data/audio_devices.bin', 0o666 | fileIo.OpenMode.CREATE);
  await fileIo.write(deviceFile.fd, deviceCompressed.buffer);
  await fileIo.close(deviceFile.fd);
  
  // 保存播放状态
  const stateStr = JSON.stringify(this.playbackState);
  const stateCompressed = await zlib.inflateSync(new Uint8Array(stateStr.split('').map(c => c.charCodeAt(0))));
  
  const stateFile = await fileIo.open('data/playback_state.bin', 0o666 | fileIo.OpenMode.CREATE);
  await fileIo.write(stateFile.fd, stateCompressed.buffer);
  await fileIo.close(stateFile.fd);
  
  // 保存连接参数
  const paramStr = JSON.stringify(this.connectionParams);
  const paramCompressed = await zlib.inflateSync(new Uint8Array(paramStr.split('').map(c => c.charCodeAt(0))));
  
  const paramFile = await fileIo.open('data/connection_params.bin', 0o666 | fileIo.OpenMode.CREATE);
  await fileIo.write(paramFile.fd, paramCompressed.buffer);
  await fileIo.close(paramFile.fd);

catch (e) {

  console.error(Failed to save local data. Code: {e.code}, message: {e.message});

}

private async initBluetooth(): Promise<void> {
try {
// 检查蓝牙是否开启
if (!bluetooth.getState()) {
await bluetooth.enable();
// 初始化A2DP Profile

  this.bluetoothA2dp = await bluetooth.getProfile(bluetooth.ProfileId.PROFILE_A2DP_SINK);
  
  // 监听蓝牙设备连接状态变化
  this.bluetoothA2dp.on('connectionStateChange', (state) => {
    this.handleDeviceConnectionChange(state);
  });
  
  // 监听音频播放状态变化
  this.bluetoothA2dp.on('playingStateChange', (state) => {
    this.handlePlayingStateChange(state);
  });
  
  // 获取已配对设备
  const bondedDevices = await bluetooth.getPairedDevices();
  this.updateDeviceList(bondedDevices);

catch (e) {

  console.error(Failed to initialize bluetooth. Code: {e.code}, message: {e.message});

}

private updateDeviceList(devices: bluetooth.Device[]): void {
devices.forEach(device => {
const existing = this.connectedDevices.find(d => d.address === device.deviceId);

  if (!existing) {
    this.connectedDevices.push({
      deviceId: 'device_' + Math.random().toString(36).substr(2, 8),
      name: device.deviceName,
      address: device.deviceId,
      isConnected: false,
      batteryLevel: 100,
      isSynced: false
    });

else {

    existing.name = device.deviceName;
    existing.isSynced = false;

});

this.saveLocalData();

private async handleDeviceConnectionChange(state: bluetooth.ProfileConnectionState): Promise<void> {

const device = this.connectedDevices.find(d => d.address === state.deviceId);
if (!device) return;

device.isConnected = state.state === bluetooth.ProfileConnectionState.STATE_CONNECTED;
device.isSynced = false;

// 连接状态变化时调整连接参数
if (device.isConnected) {
  await this.adjustConnectionParams();

await this.saveLocalData();

await this.syncData();

private async handlePlayingStateChange(state: bluetooth.AVPlaybackState): Promise<void> {

switch (state.state) {
  case bluetooth.AVPlaybackState.PLAYING:
    this.playbackState.status = 'playing';
    break;
  case bluetooth.AVPlaybackState.PAUSED:
    this.playbackState.status = 'paused';
    break;
  case bluetooth.AVPlaybackState.STOPPED:
    this.playbackState.status = 'stopped';
    break;

this.playbackState.isSynced = false;

await this.saveLocalData();
await this.syncData();

private async adjustConnectionParams(): Promise<void> {

// 根据播放状态和电池状态调整连接参数
const batteryInfo = await power.getBatteryInfo();
const isLowPower = batteryInfo.batterySoc < 30;

if (this.playbackState.status === 'playing') {
  // 播放时优化连接参数
  this.connectionParams = {
    interval: isLowPower ? 45 : 30, // 低电量时增加间隔
    latency: 0,
    timeout: 3000,
    mtu: isLowPower ? 256 : 512,    // 低电量时减小MTU
    isSynced: false
  };

else {

  // 非播放状态降低功耗
  this.connectionParams = {
    interval: 80,    // 增加连接间隔
    latency: 4,      // 增加从设备延迟
    timeout: 6000,   // 增加超时时间
    mtu: 128,        // 减小MTU
    isSynced: false
  };

// 应用新的连接参数

if (this.bluetoothA2dp) {
  try {
    await this.bluetoothA2dp.setConnectionParameters(
      this.connectionParams.interval,
      this.connectionParams.latency,
      this.connectionParams.timeout
    );
    
    await this.bluetoothA2dp.setMtu(this.connectionParams.mtu);

catch (e) {

    console.error(Failed to adjust connection params. Code: {e.code}, message: {e.message});

}

await this.saveLocalData();
await this.syncData();

public async connectDevice(deviceId: string): Promise<boolean> {

const device = this.connectedDevices.find(d => d.deviceId === deviceId);
if (!device || !this.bluetoothA2dp) return false;

try {
  await this.bluetoothA2dp.connect(device.address);
  device.isConnected = true;
  device.isSynced = false;
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to connect device. Code: {e.code}, message: {e.message});
  return false;

}

public async disconnectDevice(deviceId: string): Promise<boolean> {
const device = this.connectedDevices.find(d => d.deviceId === deviceId);
if (!device || !this.bluetoothA2dp) return false;

try {
  await this.bluetoothA2dp.disconnect(device.address);
  device.isConnected = false;
  device.isSynced = false;
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to disconnect device. Code: {e.code}, message: {e.message});
  return false;

}

public async play(): Promise<boolean> {
if (!this.bluetoothA2dp) return false;

try {
  await this.bluetoothA2dp.play();
  this.playbackState.status = 'playing';
  this.playbackState.isSynced = false;
  
  // 播放时优化连接参数
  await this.adjustConnectionParams();
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to play. Code: {e.code}, message: {e.message});
  return false;

}

public async pause(): Promise<boolean> {
if (!this.bluetoothA2dp) return false;

try {
  await this.bluetoothA2dp.pause();
  this.playbackState.status = 'paused';
  this.playbackState.isSynced = false;
  
  // 暂停时调整连接参数节省功耗
  await this.adjustConnectionParams();
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to pause. Code: {e.code}, message: {e.message});
  return false;

}

public async setVolume(volume: number): Promise<boolean> {
if (!this.bluetoothA2dp) return false;

try {
  await this.bluetoothA2dp.setVolume(volume);
  this.playbackState.volume = volume;
  this.playbackState.isSynced = false;
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to set volume. Code: {e.code}, message: {e.message});
  return false;

}

public async enterSleepMode(): Promise<boolean> {
try {
// 暂停播放
if (this.playbackState.status === ‘playing’) {
await this.pause();
// 调整连接参数进入低功耗状态

  this.connectionParams = {
    interval: 100,   // 大间隔
    latency: 6,      // 高延迟
    timeout: 10000,  // 长超时
    mtu: 64,         // 小MTU
    isSynced: false
  };
  
  await this.adjustConnectionParams();
  
  // 启用设备低功耗模式
  await power.enablePowerMode(power.PowerMode.LOW_POWER, 'Bluetooth speaker sleep mode');
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to enter sleep mode. Code: {e.code}, message: {e.message});
  return false;

}

public async wakeFromSleep(): Promise<boolean> {
try {
// 禁用低功耗模式
await power.disablePowerMode(power.PowerMode.LOW_POWER);

  // 恢复优化连接参数
  await this.adjustConnectionParams();
  
  await this.saveLocalData();
  await this.syncData();
  
  return true;

catch (e) {

  console.error(Failed to wake from sleep. Code: {e.code}, message: {e.message});
  return false;

}

private async syncData(): Promise<void> {
if (!this.kvStore) return;

try {
  // 同步设备列表
  const unsyncedDevices = this.connectedDevices.filter(d => !d.isSynced);
  if (unsyncedDevices.length > 0) {
    await this.kvStore.put('audio_devices', { value: unsyncedDevices });
    this.connectedDevices.forEach(d => {
      if (!d.isSynced) d.isSynced = true;
    });

// 同步播放状态

  if (!this.playbackState.isSynced) {
    await this.kvStore.put('playback_state', { value: this.playbackState });
    this.playbackState.isSynced = true;

// 同步连接参数

  if (!this.connectionParams.isSynced) {
    await this.kvStore.put('connection_params', { value: this.connectionParams });
    this.connectionParams.isSynced = true;

} catch (e) {

  console.error(Failed to sync data. Code: {e.code}, message: {e.message});

}

private handleRemoteDataChange(data: distributedData.ChangeData): void {
data.insertEntries.forEach((entry: distributedData.Entry) => {
if (entry.key === ‘audio_devices’) {
const remoteDevices = entry.value.value as AudioDevice[];
this.mergeDeviceList(remoteDevices);
else if (entry.key === ‘playback_state’) {

    const remoteState = entry.value.value as PlaybackState;
    this.mergePlaybackState(remoteState);

else if (entry.key === ‘connection_params’) {

    const remoteParams = entry.value.value as ConnectionParams;
    this.mergeConnectionParams(remoteParams);

});

private mergeDeviceList(remoteDevices: AudioDevice[]): void {

remoteDevices.forEach(remote => {
  const existing = this.connectedDevices.find(local => local.deviceId === remote.deviceId);
  
  if (!existing) {
    this.connectedDevices.push(remote);

else {

    // 合并策略：保留更新的连接状态
    if (remote.isConnected !== existing.isConnected) {
      existing.isConnected = remote.isConnected;

// 合并电池电量

    if (remote.batteryLevel < existing.batteryLevel) {
      existing.batteryLevel = remote.batteryLevel;

}

});

private mergePlaybackState(remoteState: PlaybackState): void {

// 合并策略：保留播放进度和状态
if (remoteState.status !== this.playbackState.status) {
  this.playbackState.status = remoteState.status;

if (Math.abs(remoteState.currentPosition - this.playbackState.currentPosition) > 1000) {

  this.playbackState.currentPosition = remoteState.currentPosition;

if (remoteState.volume !== this.playbackState.volume) {

  this.playbackState.volume = remoteState.volume;

}

private mergeConnectionParams(remoteParams: ConnectionParams): void {
// 合并策略：采用更节能的参数
this.connectionParams.interval = Math.max(
this.connectionParams.interval,
remoteParams.interval
);

this.connectionParams.latency = Math.max(
  this.connectionParams.latency,
  remoteParams.latency
);

this.connectionParams.timeout = Math.max(
  this.connectionParams.timeout,
  remoteParams.timeout
);

this.connectionParams.mtu = Math.min(
  this.connectionParams.mtu,
  remoteParams.mtu
);

public getConnectedDevices(): AudioDevice[] {

return this.connectedDevices.filter(d => d.isConnected);

public getPlaybackState(): PlaybackState {

return this.playbackState;

public getConnectionParams(): ConnectionParams {

return this.connectionParams;

public async destroy(): Promise<void> {

if (this.bluetoothA2dp) {
  this.bluetoothA2dp.off('connectionStateChange');
  this.bluetoothA2dp.off('playingStateChange');

if (this.audioRenderer) {

  await this.audioRenderer.release();
  this.audioRenderer = null;

if (this.kvStore) {

  this.kvStore.off('dataChange');

await this.saveLocalData();

}

音频解码器实现 (硬件加速)

// src/main/ets/service/AudioDecoder.ts
import { BusinessError } from ‘@ohos.base’;
import { audio } from ‘@ohos.multimedia.audio’;
import { taskpool } from ‘@ohos.taskpool’;

export class AudioDecoder {
private audioRenderer: audio.AudioRenderer | null = null;
private decoder: audio.AudioDecoder | null = null;
private isHardwareAccelerated: boolean = false;

public async init(codec: audio.AudioCodecFormat): Promise<boolean> {
try {
// 检查硬件解码器支持
const supportedCodecs = await audio.getSupportedCodecs();
this.isHardwareAccelerated = supportedCodecs.includes(codec);

  // 创建音频渲染器
  const audioRendererOptions: audio.AudioRendererOptions = {
    streamInfo: {
      samplingRate: audio.AudioSamplingRate.SAMPLE_RATE_44100,
      channels: audio.AudioChannel.CHANNEL_2,
      sampleFormat: audio.AudioSampleFormat.SAMPLE_FORMAT_S16LE,
      encodingType: audio.AudioEncodingType.ENCODING_TYPE_RAW
    },
    rendererInfo: {
      usage: audio.StreamUsage.STREAM_USAGE_MEDIA,
      rendererFlags: 0

};

  this.audioRenderer = await audio.createAudioRenderer(audioRendererOptions);
  
  // 创建解码器
  const decoderOptions: audio.AudioDecoderOptions = {
    codec: codec,
    hardwareAccelerated: this.isHardwareAccelerated
  };
  
  this.decoder = await audio.createAudioDecoder(decoderOptions);
  
  return true;

catch (e) {

  console.error(Failed to initialize decoder. Code: {e.code}, message: {e.message});
  return false;

}

public async decodeAndPlay(audioData: Uint8Array): Promise<boolean> {
if (!this.decoder || !this.audioRenderer) return false;

try {
  // 使用任务池并行解码
  const task = new taskpool.Task(this.decodeAudioTask, audioData, this.isHardwareAccelerated);
  const decodedData = await taskpool.execute(task) as ArrayBuffer;
  
  // 播放解码后的音频
  await this.audioRenderer.write(decodedData);
  
  return true;

catch (e) {

  console.error(Failed to decode and play audio. Code: {e.code}, message: {e.message});
  return false;

}

private decodeAudioTask(audioData: Uint8Array, hardwareAccelerated: boolean): ArrayBuffer {
// 模拟解码过程 (实际应用中应使用真实解码器)
const decodedSize = audioData.length * 2; // PCM数据通常比压缩数据大
const decodedData = new ArrayBuffer(decodedSize);

// 模拟硬件加速效果
if (hardwareAccelerated) {
  // 硬件解码通常更快
  for (let i = 0; i < audioData.length; i++) {
    const value = audioData[i] * 256; // 简单模拟解码过程
    new DataView(decodedData).setInt16(i * 2, value, true);

} else {

  // 软件解码
  for (let i = 0; i < audioData.length; i++) {
    const value = audioData[i] * 128; // 简单模拟解码过程
    new DataView(decodedData).setInt16(i * 2, value, true);

}

return decodedData;

public async release(): Promise<void> {

if (this.audioRenderer) {
  await this.audioRenderer.stop();
  await this.audioRenderer.release();
  this.audioRenderer = null;

if (this.decoder) {

  await this.decoder.release();
  this.decoder = null;

}

蓝牙音箱组件实现

// src/main/ets/components/BluetoothSpeaker.ets
@Component
export struct BluetoothSpeaker {
private btService = BluetoothAudioService.getInstance();
private audioDecoder = new AudioDecoder();
@State connectedDevices: AudioDevice[] = [];
@State playbackState: PlaybackState = {
currentPosition: 0,
duration: 0,
status: ‘stopped’,
volume: 80,
isSynced: false
};
@State connectionParams: ConnectionParams = {
interval: 30,
latency: 0,
timeout: 3000,
mtu: 512,
isSynced: false
};
@State isSleepMode: boolean = false;
private timer: number = 0;

aboutToAppear(): void {
this.loadData();
this.startAutoRefresh();
this.initDecoder();
aboutToDisappear(): void {

this.stopAutoRefresh();
this.audioDecoder.release();

private async loadData(): Promise<void> {

this.connectedDevices = this.btService.getConnectedDevices();
this.playbackState = this.btService.getPlaybackState();
this.connectionParams = this.btService.getConnectionParams();

private async initDecoder(): Promise<void> {

await this.audioDecoder.init(audio.AudioCodecFormat.AAC);

private startAutoRefresh(): void {

this.timer = setInterval(() => {
  this.loadData();
}, 1000); // 每秒刷新一次

private stopAutoRefresh(): void {

if (this.timer) {
  clearInterval(this.timer);
  this.timer = 0;

}

build() {
Column() {
// 标题
Text(‘蓝牙音箱控制’)
.fontSize(24)
.fontWeight(FontWeight.Bold)
.margin({ bottom: 20 });

  // 设备状态卡片
  this.buildDeviceCard();
  
  // 播放控制
  this.buildPlaybackControls();
  
  // 连接参数
  Text('连接参数')
    .fontSize(18)
    .fontWeight(FontWeight.Bold)
    .margin({ top: 20, bottom: 10 });
  
  this.buildConnectionParams();
  
  // 睡眠模式控制
  Button(this.isSleepMode ? '唤醒音箱' : '进入睡眠模式')
    .type(ButtonType.Capsule)
    .width('80%')
    .height(50)
    .backgroundColor(this.isSleepMode ? '#4CAF50' : '#9E9E9E')
    .fontColor('#FFFFFF')
    .margin({ top: 30 })
    .onClick(() => {
      this.toggleSleepMode();
    });

.width(‘100%’)

.height('100%')
.padding(20);

@Builder

private buildDeviceCard() {
Column() {
if (this.connectedDevices.length > 0) {
ForEach(this.connectedDevices, (device) => {
Column() {
Row() {
Image($r(‘app.media.ic_speaker’))
.width(40)
.height(40)
.margin({ right: 10 });

          Column() {
            Text(device.name)
              .fontSize(16)
              .fontWeight(FontWeight.Bold);
            
            Row() {
              Text('电量:')
                .fontSize(12)
                .fontColor('#666666');
              
              Text(${device.batteryLevel}%)
                .fontSize(12)
                .fontColor('#666666')
                .margin({ left: 5 });

}

          .layoutWeight(1);
          
          Button('断开')
            .type(ButtonType.Circle)
            .width(40)
            .height(40)
            .backgroundColor('#F44336')
            .fontColor('#FFFFFF')
            .onClick(() => {
              this.disconnectDevice(device.deviceId);
            });

.width(‘100%’)

        .padding(10)

.backgroundColor(‘#FFFFFF’)

      .borderRadius(10)
      .shadow({ radius: 3, color: '#E0E0E0', offsetX: 0, offsetY: 1 })
      .margin({ bottom: 10 });
    })

else {

    Text('未连接设备')
      .fontSize(16)
      .fontColor('#666666');

}

.width('100%')
.padding(15)
.backgroundColor('#F5F5F5')
.borderRadius(10)
.shadow({ radius: 5, color: '#E0E0E0', offsetX: 0, offsetY: 2 });

@Builder

private buildPlaybackControls() {
Column() {
// 播放进度
Row() {
Text(this.formatTime(this.playbackState.currentPosition))
.fontSize(14)
.fontColor(‘#666666’);

    Slider({
      value: this.playbackState.currentPosition,
      min: 0,
      max: this.playbackState.duration,
      step: 1000,
      style: SliderStyle.OutSet
    })
    .blockColor('#2196F3')
    .trackThickness(8)
    .trackColor('#E0E0E0')
    .selectedColor('#2196F3')
    .width('60%')
    .margin({ left: 10, right: 10 })
    .onChange((value: number) => {
      this.seekTo(value);
    });
    
    Text(this.formatTime(this.playbackState.duration))
      .fontSize(14)
      .fontColor('#666666');

.width(‘100%’)

  .margin({ bottom: 20 });
  
  // 控制按钮
  Row() {
    Button('上一首')
      .type(ButtonType.Circle)
      .width(60)
      .height(60)
      .backgroundColor('#FFFFFF')
      .fontColor('#2196F3')
      .onClick(() => {
        this.previousTrack();
      });
    
    Button(this.playbackState.status === 'playing' ? '暂停' : '播放')
      .type(ButtonType.Circle)
      .width(80)
      .height(80)
      .backgroundColor('#2196F3')
      .fontColor('#FFFFFF')
      .margin({ left: 20, right: 20 })
      .onClick(() => {
        this.togglePlayback();
      });
    
    Button('下一首')
      .type(ButtonType.Circle)
      .width(60)
      .height(60)
      .backgroundColor('#FFFFFF')
      .fontColor('#2196F3')
      .onClick(() => {
        this.nextTrack();
      });

.width(‘100%’)

  .justifyContent(FlexAlign.Center)
  .margin({ bottom: 20 });
  
  // 音量控制
  Row() {
    Image($r('app.media.ic_volume'))
      .width(24)
      .height(24)
      .margin({ right: 10 });
    
    Slider({
      value: this.playbackState.volume,
      min: 0,
      max: 100,
      step: 5,
      style: SliderStyle.OutSet
    })
    .blockColor('#2196F3')
    .trackThickness(8)
    .trackColor('#E0E0E0')
    .selectedColor('#2196F3')
    .width('70%')
    .onChange((value: number) => {
      this.setVolume(value);
    });

.width(‘100%’);

.width(‘100%’)

.padding(15)
.backgroundColor('#FFFFFF')
.borderRadius(10)
.shadow({ radius: 5, color: '#E0E0E0', offsetX: 0, offsetY: 2 });

private formatTime(ms: number): string {

const seconds = Math.floor(ms / 1000);
const minutes = Math.floor(seconds / 60);
const remainingSeconds = seconds % 60;

return {minutes}:{remainingSeconds < 10 ? '0' : ''}${remainingSeconds};

@Builder

private buildConnectionParams() {
Column() {
Row() {
Text(‘连接间隔:’)
.fontSize(14)
.fontColor(‘#666666’)
.margin({ right: 10 });

    Text(${this.connectionParams.interval}ms)
      .fontSize(14)
      .fontColor('#2196F3');

.margin({ bottom: 5 });

  Row() {
    Text('从设备延迟:')
      .fontSize(14)
      .fontColor('#666666')
      .margin({ right: 10 });
    
    Text(${this.connectionParams.latency})
      .fontSize(14)
      .fontColor('#2196F3');

.margin({ bottom: 5 });

  Row() {
    Text('超时时间:')
      .fontSize(14)
      .fontColor('#666666')
      .margin({ right: 10 });
    
    Text(${this.connectionParams.timeout}ms)
      .fontSize(14)
      .fontColor('#2196F3');

.margin({ bottom: 5 });

  Row() {
    Text('MTU大小:')
      .fontSize(14)
      .fontColor('#666666')
      .margin({ right: 10 });
    
    Text(${this.connectionParams.mtu}字节)
      .fontSize(14)
      .fontColor('#2196F3');

}

.width('100%')
.padding(15)
.backgroundColor('#FFFFFF')
.borderRadius(10)
.shadow({ radius: 5, color: '#E0E0E0', offsetX: 0, offsetY: 2 });

private async togglePlayback(): Promise<void> {

if (this.playbackState.status === 'playing') {
  await this.btService.pause();

else {

  await this.btService.play();

this.loadData();

private async previousTrack(): Promise<void> {

// 实际应用中应实现切歌逻辑
prompt.showToast({ message: '切换到上一首', duration: 1000 });
this.playbackState.currentPosition = 0;
await this.btService.play();
this.loadData();

private async nextTrack(): Promise<void> {

// 实际应用中应实现切歌逻辑
prompt.showToast({ message: '切换到下一首', duration: 1000 });
this.playbackState.currentPosition = 0;
await this.btService.play();
this.loadData();

private async seekTo(position: number): Promise<void> {

// 实际应用中应实现跳转逻辑
this.playbackState.currentPosition = position;
prompt.showToast({ message: 跳转到 ${this.formatTime(position)}, duration: 1000 });

private async setVolume(volume: number): Promise<void> {

await this.btService.setVolume(volume);
this.playbackState.volume = volume;

private async connectDevice(deviceId: string): Promise<void> {

const success = await this.btService.connectDevice(deviceId);
if (success) {
  prompt.showToast({ message: '设备连接成功', duration: 2000 });
  this.loadData();

else {

  prompt.showToast({ message: '设备连接失败', duration: 2000 });

}

private async disconnectDevice(deviceId: string): Promise<void> {
const success = await this.btService.disconnectDevice(deviceId);
if (success) {
prompt.showToast({ message: ‘设备已断开’, duration: 2000 });
this.loadData();
else {

  prompt.showToast({ message: '断开设备失败', duration: 2000 });

}

private async toggleSleepMode(): Promise<void> {
if (this.isSleepMode) {
const success = await this.btService.wakeFromSleep();
if (success) {
this.isSleepMode = false;
prompt.showToast({ message: ‘音箱已唤醒’, duration: 2000 });
} else {

  const success = await this.btService.enterSleepMode();
  if (success) {
    this.isSleepMode = true;
    prompt.showToast({ message: '音箱进入睡眠模式', duration: 2000 });

}

主界面实现

// src/main/ets/pages/AudioPage.ets
import { BluetoothAudioService } from ‘…/service/BluetoothAudioService’;
import { BluetoothSpeaker } from ‘…/components/BluetoothSpeaker’;

@Entry
@Component
struct AudioPage {
@State activeTab: number = 0;
private btService = BluetoothAudioService.getInstance();

build() {
Column() {
// 标题
Text(‘智能音箱系统’)
.fontSize(24)
.fontWeight(FontWeight.Bold)
.margin({ bottom: 20 });

  // 标签页
  Tabs({ barPosition: BarPosition.Start }) {
    TabContent() {
      // 音箱控制标签页
      BluetoothSpeaker()

.tabBar(‘音箱控制’);

    TabContent() {
      // 设备管理标签页
      this.buildDeviceTab()

.tabBar(‘设备管理’);

.barWidth(‘100%’)

  .barHeight(50)
  .width('100%')
  .height('80%')

.width(‘100%’)

.height('100%')
.padding(20);

@Builder

private buildDeviceTab() {
Column() {
Text(‘可用设备’)
.fontSize(20)
.fontWeight(FontWeight.Bold)
.margin({ bottom: 20 });

  List({ space: 10 }) {
    ForEach(this.btService.getConnectedDevices(), (device) => {
      ListItem() {
        Row() {
          Image($r('app.media.ic_bluetooth'))
            .width(40)
            .height(40)
            .margin({ right: 10 });
          
          Column() {
            Text(device.name)
              .fontSize(16)
              .fontWeight(FontWeight.Bold);
            
            Text(电量: ${device.batteryLevel}%)
              .fontSize(14)
              .fontColor('#666666');

.layoutWeight(1);

          if (device.isConnected) {
            Text('已连接')
              .fontSize(14)
              .fontColor('#4CAF50');

else {

            Button('连接')
              .type(ButtonType.Capsule)
              .width(80)
              .height(30)
              .backgroundColor('#2196F3')
              .fontColor('#FFFFFF')
              .onClick(() => {
                this.connectDevice(device.deviceId);
              });

}

        .width('100%')
        .padding(10)

.borderRadius(10)

      .backgroundColor('#FFFFFF')
      .shadow({ radius: 3, color: '#E0E0E0', offsetX: 0, offsetY: 1 });
    })

.width(‘100%’)

  .height('70%');
  
  Button('扫描设备')
    .type(ButtonType.Capsule)
    .width('80%')
    .height(50)
    .backgroundColor('#2196F3')
    .fontColor('#FFFFFF')
    .margin({ top: 30 })
    .onClick(() => {
      this.scanDevices();
    });

.width(‘100%’)

.height('100%')
.padding(20);

private async scanDevices(): Promise<void> {

prompt.showToast({ message: '正在扫描蓝牙设备...', duration: 2000 });

try {
  await bluetooth.startBluetoothDiscovery();
  setTimeout(() => {
    bluetooth.stopBluetoothDiscovery();
    prompt.showToast({ message: '扫描完成', duration: 2000 });
  }, 10000); // 扫描10秒

catch (e) {

  console.error(Failed to scan devices. Code: {e.code}, message: {e.message});
  prompt.showToast({ message: '扫描失败', duration: 2000 });

}

private async connectDevice(deviceId: string): Promise<void> {
const success = await this.btService.connectDevice(deviceId);
if (success) {
prompt.showToast({ message: ‘连接成功’, duration: 2000 });
else {

  prompt.showToast({ message: '连接失败', duration: 2000 });

}

四、与游戏同步技术的结合点
实时状态同步：借鉴游戏中玩家状态实时同步机制，优化多音箱播放状态同步

事件广播机制：类似游戏中的事件广播，实现控制指令的快速扩散

数据压缩传输：使用类似游戏中的网络优化技术，对音频控制指令进行高效传输

设备角色分配：参考游戏中的主机/客户端模式，确定主控音箱和从属音箱

状态一致性保障：借鉴游戏中的状态同步机制，确保多设备间播放状态一致

五、关键特性实现
音频解码硬件加速：

  public async init(codec: audio.AudioCodecFormat): Promise<boolean> {
 // 检查硬件解码器支持
 const supportedCodecs = await audio.getSupportedCodecs();
 this.isHardwareAccelerated = supportedCodecs.includes(codec);
 
 // 创建解码器时启用硬件加速
 const decoderOptions: audio.AudioDecoderOptions = {
   codec: codec,
   hardwareAccelerated: this.isHardwareAccelerated
 };
 
 this.decoder = await audio.createAudioDecoder(decoderOptions);
 return true;

蓝牙连接参数动态调整：

  private async adjustConnectionParams(): Promise<void> {
 const batteryInfo = await power.getBatteryInfo();
 const isLowPower = batteryInfo.batterySoc < 30;
 
 if (this.playbackState.status === 'playing') {
   // 播放时优化连接参数
   this.connectionParams = {
     interval: isLowPower ? 45 : 30, // 低电量时增加间隔
     latency: 0,
     timeout: 3000,
     mtu: isLowPower ? 256 : 512,    // 低电量时减小MTU
     isSynced: false
   };

else {

   // 非播放状态降低功耗
   this.connectionParams = {
     interval: 80,    // 增加连接间隔
     latency: 4,      // 增加从设备延迟
     timeout: 6000,   // 增加超时时间
     mtu: 128,        // 减小MTU
     isSynced: false
   };

// 应用新的连接参数

 if (this.bluetoothA2dp) {
   await this.bluetoothA2dp.setConnectionParameters(
     this.connectionParams.interval,
     this.connectionParams.latency,
     this.connectionParams.timeout
   );
   await this.bluetoothA2dp.setMtu(this.connectionParams.mtu);

}

休眠模式快速恢复：

  public async wakeFromSleep(): Promise<boolean> {
 try {
   // 禁用低功耗模式
   await power.disablePowerMode(power.PowerMode.LOW_POWER);
   
   // 快速恢复优化连接参数
   this.connectionParams = {
     interval: 30,
     latency: 0,
     timeout: 3000,
     mtu: 512,
     isSynced: false
   };
   
   await this.adjustConnectionParams();
   return true;

catch (e) {

   console.error(Failed to wake from sleep. Code: {e.code}, message: {e.message});
   return false;

}

多设备音频同步：

  private mergePlaybackState(remoteState: PlaybackState): void {
 // 合并策略：保留播放进度和状态
 if (remoteState.status !== this.playbackState.status) {
   this.playbackState.status = remoteState.status;

// 如果时间差小于100ms则忽略，大于1秒则同步

 if (Math.abs(remoteState.currentPosition - this.playbackState.currentPosition) > 1000) {
   this.playbackState.currentPosition = remoteState.currentPosition;

// 同步音量

 if (remoteState.volume !== this.playbackState.volume) {
   this.playbackState.volume = remoteState.volume;

}

六、性能优化策略
智能数据同步：

  // 只有新数据时才触发同步

if (now - this.lastSyncTime > this.SYNC_INTERVAL) {
await this.syncData();
this.lastSyncTime = now;

本地缓存优先：

  public getConnectedDevices(): AudioDevice[] {
 // 先从内存缓存读取
 return this.connectedDevices.filter(d => d.isConnected);

并行解码优化：

  // 使用任务池并行解码音频数据

const task = new taskpool.Task(this.decodeAudioTask, audioData, this.isHardwareAccelerated);
const decodedData = await taskpool.execute(task) as ArrayBuffer;

资源释放管理：

  public async destroy(): Promise<void> {
 if (this.bluetoothA2dp) {
   this.bluetoothA2dp.off('connectionStateChange');
   this.bluetoothA2dp.off('playingStateChange');

if (this.audioRenderer) {