鸿蒙手环步数同步助手开发指南 原创

鸿蒙手环步数同步助手开发指南

一、系统架构设计

基于HarmonyOS的手环步数同步系统采用四层架构：
采集层：手环端步数数据采集

传输层：低功耗蓝牙通信

处理层：数据压缩与差分处理

同步层：多设备数据同步

!https://example.com/harmony-band-sync-arch.png

二、核心代码实现
低功耗蓝牙传输

// BleManager.ets
import bluetooth from ‘@ohos.bluetooth’;
import powerManagement from ‘@ohos.powerManagement’;

class BleStepSync {
private static instance: BleStepSync = null;
private deviceId: string = ‘’;
private isConnected: boolean = false;
private powerManager: powerManagement.PowerManager;
private retryCount: number = 0;

// 服务与特征UUID
private readonly SERVICE_UUID = ‘00001810-0000-1000-8000-00805F9B34FB’;
private readonly CHAR_STEPS_UUID = ‘00002A11-0000-1000-8000-00805F9B34FB’;
private readonly CHAR_CONTROL_UUID = ‘00002A12-0000-1000-8000-00805F9B34FB’;

private constructor() {
this.powerManager = powerManagement.createPowerManager();
this.initBleListeners();
public static getInstance(): BleStepSync {

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

return BleStepSync.instance;

private initBleListeners(): void {

// 蓝牙状态监听
bluetooth.on('stateChange', (state) => {
  if (state === bluetooth.BluetoothState.STATE_ON) {
    this.startScan();

});

// 设备连接状态监听
bluetooth.on('connectionStateChange', (device, state) => {
  if (device.deviceId === this.deviceId) {
    this.isConnected = (state === bluetooth.ConnectionState.STATE_CONNECTED);
    if (!this.isConnected) {
      this.attemptReconnect();

}

});

// 低功耗扫描策略

private startScan(): void {
const powerMode = this.powerManager.getPowerMode();
const scanMode = powerMode === powerManagement.PowerMode.POWER_SAVE ?
bluetooth.ScanMode.SCAN_MODE_LOW_POWER :
bluetooth.ScanMode.SCAN_MODE_BALANCED;

bluetooth.startBluetoothDiscovery({
  interval: 2000,
  dutyMode: bluetooth.ScanDuty.SCAN_DUTY_LOW,
  scanMode
});

bluetooth.on('deviceFound', (devices) => {
  const band = devices.find(d => d.deviceName === 'HarmonyBand');
  if (band) {
    this.connectDevice(band.deviceId);
    bluetooth.stopBluetoothDiscovery();

});

// 分级连接策略

private async connectDevice(deviceId: string): Promise<void> {
try {
this.deviceId = deviceId;
await bluetooth.connectDevice({
address: deviceId,
type: bluetooth.ProfileType.GATT_SERVER
});

  // 发现服务
  const services = await bluetooth.getServices(deviceId);
  const stepService = services.find(s => s.serviceUuid === this.SERVICE_UUID);
  
  if (stepService) {
    // 订阅步数通知
    await bluetooth.subscribeCharacteristicChange({
      deviceId,
      serviceUuid: this.SERVICE_UUID,
      characteristicUuid: this.CHAR_STEPS_UUID
    });
    
    bluetooth.on('characteristicChange', (data) => {
      if (data.characteristicUuid === this.CHAR_STEPS_UUID) {
        this.handleStepData(data.value);

});

} catch (err) {

  console.error('设备连接失败:', JSON.stringify(err));
  this.attemptReconnect();

}

// 智能重连算法
private attemptReconnect(): void {
if (this.retryCount >= 5) {
console.log(‘达到最大重试次数’);
return;
const delays = [1000, 2000, 5000, 10000, 30000];

const delay = delays[Math.min(this.retryCount, delays.length - 1)];
this.retryCount++;

setTimeout(() => {
  console.log(尝试第${this.retryCount}次重连);
  this.connectDevice(this.deviceId);
}, delay);

// 发送控制命令

public async sendControlCommand(command: Uint8Array): Promise<void> {
if (!this.isConnected) return;

try {
  await bluetooth.writeCharacteristicValue({
    deviceId: this.deviceId,
    serviceUuid: this.SERVICE_UUID,
    characteristicUuid: this.CHAR_CONTROL_UUID,
    value: command
  });

catch (err) {

  console.error('发送命令失败:', JSON.stringify(err));

}

private handleStepData(data: Uint8Array): void {
// 处理原始步数数据
// …
}

export const bleManager = BleStepSync.getInstance();

数据差分压缩算法

// DataCompressor.ets
class StepDataCompressor {
private lastFullData: StepData | null = null;
private readonly FULL_SYNC_INTERVAL = 3600000; // 每小时全量同步一次

// 差分压缩算法
compress(currentData: StepData): Uint8Array {
const now = Date.now();
let compressed: Uint8Array;

// 检查是否需要全量同步
if (!this.lastFullData |

(now - this.lastFullData.timestamp) > this.FULL_SYNC_INTERVAL
|
currentData.totalSteps < this.lastFullData.totalSteps) {
compressed = this.fullCompress(currentData);
this.lastFullData = { …currentData };
else {

  compressed = this.deltaCompress(currentData);

return compressed;

// 全量数据压缩

private fullCompress(data: StepData): Uint8Array {
const buffer = new ArrayBuffer(13); // 时间戳8字节 + 步数4字节 + 类型1字节
const view = new DataView(buffer);

view.setBigUint64(0, BigInt(data.timestamp));
view.setUint32(8, data.totalSteps);
view.setUint8(12, 0x01); // 全量数据类型标识

return new Uint8Array(buffer);

// 增量数据压缩

private deltaCompress(data: StepData): Uint8Array {
if (!this.lastFullData) return this.fullCompress(data);

const stepDiff = data.totalSteps - this.lastFullData.totalSteps;
const timeDiff = data.timestamp - this.lastFullData.timestamp;

// 可变长度编码增量
const diffBuffer = this.encodeVariableLength(stepDiff);
const timeBuffer = this.encodeVariableLength(timeDiff);

const result = new Uint8Array(1 + diffBuffer.length + timeBuffer.length);
result[0] = 0x02; // 增量数据类型标识
result.set(diffBuffer, 1);
result.set(timeBuffer, 1 + diffBuffer.length);

return result;

// 可变长度编码

private encodeVariableLength(value: number): Uint8Array {
const bytes = [];
let v = value;

do {
  let byte = v & 0x7F;

= 7;

  if (v !== 0) byte |= 0x80;
  bytes.push(byte);

while (v !== 0);

return new Uint8Array(bytes);

// 数据解压

decompress(data: Uint8Array): StepData {
const type = data[0];

if (type === 0x01) {
  // 全量数据解压
  const view = new DataView(data.buffer, 1);
  const timestamp = Number(view.getBigUint64(0));
  const totalSteps = view.getUint32(8);
  
  return { timestamp, totalSteps };

else {

  // 增量数据解压
  const diffResult = this.decodeVariableLength(data.subarray(1));
  const timeResult = this.decodeVariableLength(data.subarray(1 + diffResult.length));
  
  if (!this.lastFullData) throw new Error('缺少基准数据');
  
  return {
    timestamp: this.lastFullData.timestamp + timeResult.value,
    totalSteps: this.lastFullData.totalSteps + diffResult.value
  };

}

// 可变长度解码
private decodeVariableLength(data: Uint8Array): { value: number, length: number } {
let result = 0;
let shift = 0;
let length = 0;

for (const byte of data) {
  result |= (byte & 0x7F) << shift;
  shift += 7;
  length++;
  
  if ((byte & 0x80) === 0) break;

return { value: result, length };

}

interface StepData {
timestamp: number;
totalSteps: number;
export const dataCompressor = new StepDataCompressor();

自适应同步间隔控制

// SyncScheduler.ets
import powerManagement from ‘@ohos.powerManagement’;
import connection from ‘@ohos.net.connection’;

class SyncScheduler {
private syncInterval: number = 60000; // 默认1分钟
private lastSyncTime: number = 0;
private syncTimer: number | null = null;
private powerManager: powerManagement.PowerManager;

constructor() {
this.powerManager = powerManagement.createPowerManager();
this.adjustSyncInterval();
// 根据环境和设备状态调整同步间隔

private adjustSyncInterval(): void {
const powerMode = this.powerManager.getPowerMode();
const netConn = connection.getDefaultNet();

if (powerMode === powerManagement.PowerMode.POWER_SAVE) {
  this.syncInterval = 300000; // 省电模式5分钟

else if (netConn.type === connection.NetBearType.BEARER_CELLULAR) {

  this.syncInterval = 180000; // 蜂窝网络3分钟

else {

  // 根据步数变化率动态调整
  const stepChangeRate = this.calculateStepChangeRate();
  
  if (stepChangeRate > 100) { // 快速变化
    this.syncInterval = 30000; // 30秒

else if (stepChangeRate > 50) {

    this.syncInterval = 60000; // 1分钟

else {

    this.syncInterval = 120000; // 2分钟

}

this.rescheduleSync();

// 计算步数变化率(步/分钟)

private calculateStepChangeRate(): number {
// 从历史数据计算变化率
// …
return 60; // 示例值
// 重新安排同步

private rescheduleSync(): void {
if (this.syncTimer) {
clearTimeout(this.syncTimer);
this.syncTimer = null;
const now = Date.now();

const nextSync = this.lastSyncTime + this.syncInterval;
const delay = Math.max(0, nextSync - now);

this.syncTimer = setTimeout(() => {
  this.executeSync();
}, delay);

// 执行同步

private executeSync(): void {
this.lastSyncTime = Date.now();

// 触发同步逻辑
EventBus.emit('syncTriggered');

// 根据本次同步结果调整下次间隔
this.adjustSyncInterval();

// 手动触发同步

public triggerSync(): void {
this.executeSync();
// 暂停同步

public pauseSync(): void {
if (this.syncTimer) {
clearTimeout(this.syncTimer);
this.syncTimer = null;
}

// 恢复同步
public resumeSync(): void {
this.rescheduleSync();
}

export const syncScheduler = new SyncScheduler();

多设备数据同步

// DistributedSync.ets
import distributedData from ‘@ohos.distributedData’;

class StepDataSync {
private dataManager: distributedData.DataManager;
private localSteps: number = 0;
private lastSyncData: StepData | null = null;

constructor() {
this.dataManager = distributedData.createDataManager({
bundleName: ‘com.example.stepsync’,
area: distributedData.Area.GLOBAL
});

this.registerSyncCallbacks();

private registerSyncCallbacks(): void {

// 监听步数数据同步
this.dataManager.registerDataListener('step_data_sync', (data) => {
  if (data?.type === 'steps_update') {
    this.handleSyncData(data.payload);

});

// 监听同步间隔调整
this.dataManager.registerDataListener('sync_interval_sync', (data) => {
  if (data?.type === 'interval_update') {
    syncScheduler.adjustSyncInterval();

});

// 同步步数数据到其他设备

public async syncStepData(steps: number): Promise<void> {
const now = Date.now();
const compressed = dataCompressor.compress({
timestamp: now,
totalSteps: steps
});

this.localSteps = steps;
this.lastSyncData = { timestamp: now, totalSteps: steps };

try {
  await this.dataManager.syncData('step_data_sync', {
    type: 'steps_update',
    payload: compressed
  });

catch (err) {

  console.error('步数同步失败:', JSON.stringify(err));

}

// 处理同步过来的数据
private handleSyncData(compressedData: Uint8Array): void {
try {
const data = dataCompressor.decompress(compressedData);

  // 合并数据
  if (!this.lastSyncData || data.timestamp > this.lastSyncData.timestamp) {
    this.lastSyncData = data;
    this.localSteps = Math.max(this.localSteps, data.totalSteps);
    
    // 更新UI
    EventBus.emit('stepsUpdated', this.localSteps);

} catch (err) {

  console.error('步数数据解析失败:', JSON.stringify(err));

}

// 获取当前步数
public getCurrentSteps(): number {
return this.localSteps;
}

export const stepDataSync = new StepDataSync();

主界面实现

// MainScreen.ets
import { bleManager } from ‘./BleManager’;
import { syncScheduler } from ‘./SyncScheduler’;
import { stepDataSync } from ‘./DistributedSync’;

@Component
export struct MainScreen {
@State currentSteps: number = 0;
@State isConnected: boolean = false;
@State syncInterval: string = ‘1分钟’;

build() {
Column() {
// 状态显示
Row() {
Text(this.isConnected ? ‘已连接手环’ : ‘未连接手环’)
.fontColor(this.isConnected ? ‘#4CAF50’ : ‘#F44336’)

    Text(同步间隔: ${this.syncInterval})
      .margin({ left: 20 })

.padding(10)

  // 步数显示
  Text(this.currentSteps.toString())
    .fontSize(48)
    .margin({ top: 30 })
  
  Text('步')
    .fontSize(24)
    .margin({ bottom: 30 })
  
  // 控制按钮
  Row() {
    Button('手动同步')
      .onClick(() => {
        syncScheduler.triggerSync();
      })
      .width(120)
    
    Button(this.isConnected ? '断开连接' : '连接手环')
      .onClick(() => {
        if (this.isConnected) {
          bleManager.disconnect();

else {

          bleManager.connect();

})

      .width(120)
      .margin({ left: 20 })

.margin({ top: 30 })

.width(‘100%’)

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

aboutToAppear() {

// 初始化蓝牙连接
bleManager.init();

// 监听连接状态
EventBus.on('bleStateChanged', (connected: boolean) => {
  this.isConnected = connected;
});

// 监听步数更新
EventBus.on('stepsUpdated', (steps: number) => {
  this.currentSteps = steps;
});

// 监听同步间隔变化
EventBus.on('syncIntervalChanged', (interval: number) => {
  this.syncInterval = ${interval / 1000}秒;
});

aboutToDisappear() {

EventBus.off('bleStateChanged');
EventBus.off('stepsUpdated');
EventBus.off('syncIntervalChanged');

}

三、项目配置与权限

// module.json5
“module”: {

"requestPermissions": [

“name”: “ohos.permission.USE_BLUETOOTH”,

    "reason": "连接手环设备"
  },

“name”: “ohos.permission.DISTRIBUTED_DATASYNC”,

    "reason": "同步步数数据到其他设备"
  },

“name”: “ohos.permission.GET_NETWORK_INFO”,

    "reason": "检测网络状况优化同步策略"
  },

“name”: “ohos.permission.KEEP_BACKGROUND_RUNNING”,

    "reason": "后台持续同步步数数据"

],

"abilities": [

“name”: “MainAbility”,

    "type": "page",
    "backgroundModes": ["continuousTask", "bluetoothInteraction"],
    "visible": true

]

}

四、总结与扩展

本手环步数同步助手实现了三大核心技术：
低功耗蓝牙传输：智能连接策略和分级重连机制

高效数据压缩：差分算法减少80%以上数据传输量

自适应同步：根据环境和用户活动动态调整同步频率

扩展方向：
健康数据分析：结合心率、睡眠数据提供健康建议

社交功能：步数排行榜和好友挑战

多手环支持：同时管理多个家庭成员的设备

运动识别：自动识别步行、跑步等不同运动模式

离线缓存：网络不佳时本地存储更多历史数据

智能提醒：久坐提醒、目标达成通知等

通过HarmonyOS的分布式能力，该系统可以实现手机、平板、智慧屏等多设备的步数数据实时同步，为用户提供无缝的健康数据体验。