鸿蒙next 蓝牙连接穿戴设备数据交互流程_鸿蒙next连接佳明手表

一、扫描周围的蓝牙设备

1.检查app是否有授予蓝牙权限
获取apptokenId,然后判断蓝牙的可接近权限

function checkPermissions(permissions: Array): boolean { let atManager: abilityAccessCtrl.AtManager = abilityAccessCtrl.createAtManager(); // 获取应用程序的accessTokenID let tokenId: number = -1; bundleManager.getBundleInfoForSelf(bundleManager.BundleFlag.GET_BUNDLE_INFO_WITH_APPLICATION) .then((data) => { let bundleInfo: bundleManager.BundleInfo = data let appInfo: bundleManager.ApplicationInfo = bundleInfo.appInfo; tokenId = appInfo.accessTokenId; }) .catch((err: BusinessError) => { LogUtils.e(TAG, `Failed to request permissions from user. Code is ${err.code}, message is ${err.message}`); }) if (tokenId == -1) { return false } // 校验应用是否被授予权限 try { for (let i = 0; i < permissions.length; i++) { let p = permissions[i] let grantStatus = atManager.checkAccessTokenSync(tokenId, p) if (grantStatus !== abilityAccessCtrl.GrantStatus.PERMISSION_GRANTED) { return false } } } catch (error) { const err: BusinessError = error as BusinessError; LogUtils.e(TAG, `Failed to check access token. Code is ${err.code}, message is ${err.message}`); } return true;}

未开启则请求权限

function reqPermissions(permissions: Array, context: common.Context, callback: AsyncCallback) { let atManager: abilityAccessCtrl.AtManager = abilityAccessCtrl.createAtManager(); // requestPermissionsFromUser会判断权限的授权状态来决定是否唤起弹窗 atManager.requestPermissionsFromUser(context, permissions).then((data) => { let grantStatus: Array = data.authResults; let length: number = grantStatus.length; for (let i = 0; i  { LogUtils.e(TAG, `Failed to request permissions from user. Code is ${err.code}, message is ${err.message}`); callback(err, false) })}

获取权限后若系统蓝牙未开启要进行开启

 if (access.getState() == access.BluetoothState.STATE_ON) { router.pushNamedRoute({ name: RouterName.ADD_DEVICE_VIEW }) return } access.enableBluetooth() access.on(\'stateChange\', (data) => { let btStateMessage = \'\'; switch (data) {  case 2:  btStateMessage += \'STATE_ON\';  break; } if (btStateMessage == \'STATE_ON\') {  router.pushNamedRoute({ name: RouterName.ADD_DEVICE_VIEW })  return } } 

手动开启蓝牙扫描并监听蓝牙扫描结果

 ble.on(\'BLEDeviceFind\', (data) => { if (data.length  item == deviceId)) {  return } deviceList.push(deviceId) const bleName = device.deviceName if (bleNames.indexOf(device.deviceName) != -1) {  let dev = new ScanDevice(deviceId, bleName, device.rssi, device.data)  LogUtils.i(TAG, `scan device: ${JSON.stringify(dev, [\"deviceId\", \"deviceName\", \"rssi\"])}`)  callback(null, dev) } });ble.startBLEScan([scanFilter], scanOptions);

二、与蓝牙穿戴设备进行连接

连接之前为app开启后台长时任务防止app在后台被挂起或者冻结，导致收不到设备指令

 startBLEContinuousTask(deviceId: string, deviceName: string, mac: string) { let wantAgentInfo: wantAgent.WantAgentInfo = { wants: [ { bundleName: this.context.applicationInfo.name, abilityName: \"EntryAbility\" } ], operationType: wantAgent.OperationType.START_ABILITY, requestCode: 0, wantAgentFlags: [wantAgent.WantAgentFlags.UPDATE_PRESENT_FLAG] }; try { wantAgent.getWantAgent(wantAgentInfo).then((wantAgentObj) => { // 开启任务后台长时间运行 try { backgroundTaskManager.startBackgroundRunning( this.context, backgroundTaskManager.BackgroundMode.BLUETOOTH_INTERACTION, wantAgentObj ).then(() => { console.info(\"Operation startBackgroundRunning succeeded\"); WKBleMgr.connectByDeviceId(deviceId, deviceName, mac) }) } catch (error) { console.error(`Operation startBackgroundRunning failed. Code: ${error.code}, Message: ${error.message}`); } }); } catch (error) { console.error(`Operation getWantAgent failed. Code: ${error.code}, Message: ${error.message}`); } }

建立蓝牙连接

const device: ble.GattClientDevice = ble.createGattClientDevice(deviceId);device.on(\"BLEConnectionStateChange\", this.onConnectionStateChange)device.connect()

 private onConnectionStateChange = (state: ble.BLEConnectionChangeState) => { if (state.state === constant.ProfileConnectionState.STATE_CONNECTED) { setTimeout(() => { this.discoverService() }, 2 * 1000) } }

监听蓝牙特征码改变用于手表与手机之间同步数据

 this.dev.on(\"BLECharacteristicChange\", this.onCharacteristicChange) this.dev.setCharacteristicChangeNotification(characteristics, true, (err) => { if (err) { LogUtils.i(TAG, `notify fail code: ${err.code}, message: ${err.message}`); this.notifyCallback?.onNotifyFail(this.device.deviceId, new BleError(-100, \"notify fail setCharacteristic fail\")) return } LogUtils.i(TAG, `notify success`); this.notifyCallback?.onNotifySuccess(this.device.deviceId) }) onNotifySuccess(){ mgr.writeCommand(WKCommand.sendPhoneSystem()) } onCharacteristicChange(characteristic: ble.BLECharacteristic){ let value = characteristic.characteristicValue; this.notifyCallback?.onCharacteristicChanged(value) } onCharacteristicChanged: (data: ArrayBuffer): void => { const mac = this.getConnectedMac() const dataView = new Uint8Array(data) const first = dataView[0] let realData = data if (first == 0xAB || first == 0xEA || this.packager.isPackageIng()) { if (!this.packager.packageData(data)) {  return } realData = this.packager.getData() this.packager.clear() } LogUtils.i(TAG, `receive <<<<<< ${BleUtils.bytesToHex(realData)}`) for (let parser of this.parsers) { parser.onParser(mac ? mac : \"\", realData) } }

三、数据交互

我们以正常同步数据为例一般是为蓝牙设备写入特征码值

 let data = \"xx\" //同步数据指令 let characteristics = service.characteristics.find((item) => item.characteristicUuid === characteristicUUID) characteristics.characteristicValue = data this.dev.writeCharacteristicValue(characteristics, ble.GattWriteType.WRITE_NO_RESPONSE, (err) => {})

触发特征码监听回调函数onCharacteristicChanged:

 onCharacteristicChanged: (data: ArrayBuffer): void => { const mac = this.getConnectedMac() const dataView = new Uint8Array(data) const first = dataView[0] let realData = data if (first == 0xAB || first == 0xEA || this.packager.isPackageIng()) { if (!this.packager.packageData(data)) {  return } realData = this.packager.getData() this.packager.clear() } LogUtils.i(TAG, `receive <<<<<< ${BleUtils.bytesToHex(realData)}`) for (let parser of this.parsers) { parser.onParser(mac ? mac : \"\", realData) } }

解析数据，以同步数据为例
以下是简化步骤

onParser(mac: string, data: ArrayBuffer) { // 例子同步心率数据 DataMgr.saveMeasureHR(mac, dataView)}saveMeasureHR(mac,data: HealthData){ DatabaseMgr.SaveHealth(data)} class DatabaseMgr { private store?: relationalStore.RdbStore = undefined // 使用鸿蒙自带的关系数据库RdbStore进行大量健康数据的持久化存储 public async initDatabase(context: Context) { relationalStore.getRdbStore(context, DB_CONFIG, (err, store) => { if (!store) {  LogUtils.i(TAG, `initDatabase fail store is undefined`)  return } this.store = store }) } private async SaveHealth(mac,data: HealthData) { try { let have = await this.haveData(\"tab_health\", data.type, data.time) if (have) {  return } const currTime = (new Date().getTime() / 1000) | 0 const buket: relationalStore.ValuesBucket = {  mac,  value: data } const result = await this.store?.insert(\"tab_health\", buket) } catch (err) { LogUtils.e(TAG, `realSaveHealth err: ${err.code}, msg: ${err.message}`) } } }