【HarmonyOS 5】鸿蒙星闪 NearLink 详解

// NearLink设备管理服务示例
import nearlink from '@ohos.nearlink';import nearlinkSle from '@ohos.nearlink.sle';import common from '@ohos.app.ability.common';
// 星闪服务管理类export class NearLinkManager {  private context: common.UIAbilityContext | undefined;  private deviceManager: nearlinkSle.SleDeviceManager | undefined;  private connectedDeviceId: string | null = null;  private dataChannel: nearlinkSle.SleDataChannel | undefined;    constructor(context: common.UIAbilityContext) {    this.context = context;  }    // 初始化星闪服务  async initNearLinkService() {    try {      // 检查并请求星闪权限      await this.checkAndRequestNearLinkPermission();            // 创建设备管理器实例      this.deviceManager = await nearlinkSle.getSleDeviceManager(this.context!);            // 注册设备状态变化监听      this.registerDeviceStateListener();            console.info('NearLink service initialized successfully');    } catch (error) {      console.error(`Failed to initialize NearLink service: ${error}`);      throw error;    }  }    // 检查并请求星闪权限  private async checkAndRequestNearLinkPermission() {    // 权限检查逻辑    // ...  }    // 开始扫描附近的星闪设备  async startDiscovery() {    if (!this.deviceManager) {      throw new Error('Device manager not initialized');    }        try {      // 配置扫描参数      const discoveryConfig = {        mode: nearlinkSle.SleDiscoveryMode.ACTIVE,        duration: 30, // 扫描持续时间(秒)        filter: {          deviceTypes: [nearlinkSle.SleDeviceType.ALL]        }      };            // 注册设备发现回调      const callback = {        onDeviceFound: (device: nearlinkSle.SleDevice) => {          console.info(`Found device: ${device.deviceName}, type: ${device.deviceType}`);          // 处理发现的设备，例如更新UI          this.onDeviceDiscovered(device);        },        onDiscoveryStateChanged: (state: number) => {          console.info(`Discovery state changed: ${state}`);        }      };            // 开始扫描      await this.deviceManager.startDiscovery(discoveryConfig, callback);      console.info('NearLink device discovery started');    } catch (error) {      console.error(`Failed to start discovery: ${error}`);      throw error;    }  }    // 处理发现的设备  private onDeviceDiscovered(device: nearlinkSle.SleDevice) {    // 这里可以添加设备过滤逻辑    // ...        // 通知UI更新设备列表    // ...  }    // 连接到指定星闪设备  async connectToDevice(deviceId: string) {    if (!this.deviceManager) {      throw new Error('Device manager not initialized');    }        try {      // 创建连接参数      const connectParams = {        timeout: 10000, // 连接超时时间(毫秒)        connectionType: nearlinkSle.SleConnectionType.DATA_CHANNEL      };            // 连接设备      const connectionResult = await this.deviceManager.connect(deviceId, connectParams);      if (connectionResult.resultCode === 0) {        this.connectedDeviceId = deviceId;        this.dataChannel = connectionResult.dataChannel;        console.info(`Connected to device: ${deviceId}`);                // 注册数据接收回调        this.registerDataReceiveListener();      } else {        console.error(`Failed to connect device, error code: ${connectionResult.resultCode}`);        throw new Error(`Connection failed: ${connectionResult.resultCode}`);      }    } catch (error) {      console.error(`Failed to connect device: ${error}`);      throw error;    }  }    // 注册数据接收监听器  private registerDataReceiveListener() {    if (!this.dataChannel) return;        this.dataChannel.on('dataReceived', (data: ArrayBuffer) => {      // 处理接收到的数据      const decoder = new TextDecoder();      const message = decoder.decode(data);      console.info(`Received data: ${message}`);            // 通知UI有新数据到达      // ...    });  }    // 发送数据到已连接设备  async sendData(message: string) {    if (!this.dataChannel) {      throw new Error('Data channel not initialized');    }        try {      const encoder = new TextEncoder();      const data = encoder.encode(message).buffer;            // 发送数据      await this.dataChannel.send(data);      console.info(`Data sent successfully: ${message}`);    } catch (error) {      console.error(`Failed to send data: ${error}`);      throw error;    }  }    // 断开与设备的连接  async disconnect() {    if (!this.deviceManager || !this.connectedDeviceId) return;        try {      await this.deviceManager.disconnect(this.connectedDeviceId);      this.connectedDeviceId = null;      this.dataChannel = undefined;      console.info('Device disconnected');    } catch (error) {      console.error(`Failed to disconnect device: ${error}`);      throw error;    }  }    // 注册设备状态变化监听  private registerDeviceStateListener() {    if (!this.deviceManager) return;        this.deviceManager.on('deviceStateChanged', (params) => {      console.info(`Device state changed: ${JSON.stringify(params)}`);      // 处理设备状态变化      // ...    });  }    // 释放资源  async release() {    await this.disconnect();        if (this.deviceManager) {      try {        await this.deviceManager.release();        console.info('NearLink resources released');      } catch (error) {        console.error(`Failed to release resources: ${error}`);      }    }  }}