微信小程序实现蓝牙开锁、开门、开关、指令发送成功，但蓝牙设备毫无反应、坑

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开源

wx联系本人获取源码(开源): MJ682517

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html

<view><view class="p_l_36 p_r_36"><input class="w_100_ h_80 lh_80 ta_c b_2s_eee radius_20" value="{{instructVal}}" type="text" placeholder="请输入开门指令" bindinput="bindinput" /></view><view class="m_t_36 w_50_ h_90 lh_90 m_l_a m_r_a bc_409eff radius_10 color_fff ta_c" catchtap="openBluetoothAdapter">蓝牙开锁</view>
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JavaScript

需要从下往上阅读，使用函数自调的方式解决API不能及时获取数据的问题，替换方案是使用定时器，但是个人觉得定时器不好，所以使用了函数自调的方式实现获取不到数据的问题。

getBluetoothDevices方法中获取deviceId；getBLEDeviceServices方法中获取到serviceId，获取到的是数组，取数组中的uuid作为serviceId值，具体用哪个值，需要与蓝牙设备文档比对；getBLEDeviceCharacteristics方法中获取characteristicId，获取到的是数组，取数组中的uuid作为characteristicId值。

一般情况的对应的值如下
serviceId: 0000FFB0-0000-1000-8000-00805F9B34FB
notifyId: 0000FFB2-0000-1000-8000-00805F9B34FB
writeId: 0000FFB1-0000-1000-8000-00805F9B34FB
注意观察第一个横杠前面最后两位的值，不难发现规律。
写入的指令一般是以十六进制(EE03E30100)字符串的方式，最后转为二进制发送给蓝牙。

坑: 在不确定蓝牙文档是否正确的情况下，写入成功，但是蓝牙设备毫无反应，那么大概率就是写入的指令有问题，所以需要校对一下指令是否正确。

蓝牙文档需要与厂商获取。

获取蓝牙服务值方法getBLEDeviceServices。
获取蓝牙特征值方法getBLEDeviceCharacteristics。特征值一般包括两个，一个代表写入值，一个代表读取值，意思是说写入的是需要把写入的特征值带上，读取的时候把读取的特征值带上。

notifyBLECharacteristicValueChange方法启用蓝牙低功耗设备特征值变化时的notify功能，订阅特征。此时传入的是读取的特征值。

// index.js
let timeout = undefined;Page({data: {devices: [],deviceId: '',services: [],serviceId: '',characteristics: [],characteristicId: '',instructVal: 'EE03E30100'},// 指令输入bindinput({detail: {value}}) {this.setData({instructVal: value});},// 失败时的统一提示failShowToast(title = '开锁失败') {clearTimeout(timeout);timeout = undefined;wx.hideLoading();wx.showToast({icon: 'none',title});},/*** 根据不同方法名调用方法，统一定时器的触发判断，* 当定时器触发时，无法确定当前调用的方法是哪个* @param {String} fnName */methodExecution(fnName = '') {if (timeout) this[fnName]();},// 关闭蓝牙模块closeBluetoothAdapter() {let that = this;// 关闭蓝牙模块wx.closeBluetoothAdapter({success() {},fail() {that.methodExecution('closeBluetoothAdapter');}});},// 断开与蓝牙低功耗设备的连接closeBLEConnection() {let that = this;// 断开与蓝牙低功耗设备的连接wx.closeBLEConnection({deviceId: that.data.deviceId,success() {that.closeBluetoothAdapter();},fail() {that.methodExecution('closeBLEConnection');}});},// 向蓝牙低功耗设备特征值中写入二进制数据writeBLECharacteristicValue() {let that = this;let str = that.data.instructVal;if (!str) return wx.showToast({title: '请输入指令',icon: 'none'});/* 将数值转为ArrayBuffer类型数据 */let typedArray = new Uint8Array(str.match(/[\da-f]{2}/gi).map((h) => parseInt(h, 16))),buffer = typedArray.buffer;// 向蓝牙低功耗设备特征值中写入二进制数据wx.writeBLECharacteristicValue({deviceId: that.data.deviceId,serviceId: that.data.serviceId,characteristicId: '0000FFB1-0000-1000-8000-00805F9B34FB',value: buffer,success() {clearTimeout(timeout);timeout = undefined;wx.hideLoading();wx.showToast({icon: 'none',title: '开锁成功'});// that.closeBLEConnection();},fail() {that.methodExecution('writeBLECharacteristicValue');}});},// 监听蓝牙低功耗设备的特征值变化事件onBLECharacteristicValueChange() {let that = this;// 监听蓝牙低功耗设备的特征值变化事件wx.onBLECharacteristicValueChange((res) => {if (res.value) {that.writeBLECharacteristicValue();} else {that.methodExecution('onBLECharacteristicValueChange');}});},// 启用蓝牙低功耗设备特征值变化时的 notify 功能，订阅特征notifyBLECharacteristicValueChange() {let that = this;// 启用蓝牙低功耗设备特征值变化时的 notify 功能，订阅特征wx.notifyBLECharacteristicValueChange({state: true,deviceId: that.data.deviceId,serviceId: that.data.serviceId,characteristicId: that.data.characteristicId,success() {that.onBLECharacteristicValueChange();},fail() {that.methodExecution('notifyBLECharacteristicValueChange');}});},// 获取蓝牙低功耗设备某个服务中所有特征 (characteristic)getBLEDeviceCharacteristics() {let that = this;// 获取蓝牙低功耗设备某个服务中所有特征 (characteristic)wx.getBLEDeviceCharacteristics({deviceId: that.data.deviceId,serviceId: that.data.serviceId,success({characteristics}) {that.setData({characteristics,characteristicId: '0000FFB2-0000-1000-8000-00805F9B34FB'}, () => that.notifyBLECharacteristicValueChange());},fail() {that.methodExecution('getBLEDeviceCharacteristics');}});},// 获取蓝牙低功耗设备所有服务 (service)getBLEDeviceServices() {let that = this;// 获取蓝牙低功耗设备所有服务 (service)wx.getBLEDeviceServices({deviceId: that.data.deviceId,success({services}) {that.setData({services,serviceId: '0000FFB0-0000-1000-8000-00805F9B34FB'}, () => that.getBLEDeviceCharacteristics());},fail() {that.methodExecution('getBLEDeviceServices');}});},// 停止搜寻附近的蓝牙外围设备stopBluetoothDevicesDiscovery() {let that = this;// 停止搜寻附近的蓝牙外围设备wx.stopBluetoothDevicesDiscovery({success() {that.getBLEDeviceServices();},fail() {that.methodExecution('stopBluetoothDevicesDiscovery');}});},// 连接蓝牙低功耗设备createBLEConnection() {let that = this;// 连接蓝牙低功耗设备wx.createBLEConnection({deviceId: that.data.deviceId,success() {that.stopBluetoothDevicesDiscovery();},fail() {that.methodExecution('createBLEConnection');}});},// 获取在蓝牙模块生效期间所有搜索到的蓝牙设备getBluetoothDevices() {let that = this;// 获取在蓝牙模块生效期间所有搜索到的蓝牙设备wx.getBluetoothDevices({success({devices}) {for (let i = 0; i < devices.length; i++) {const item = devices[i];if (item.name === 'YX_0A45320C78C6') {item.ASUUID = item.advertisServiceUUIDs[0];that.setData({devices: item,deviceId: item.deviceId}, () => that.createBLEConnection());break;}}that.methodExecution('getBluetoothDevices');},fail() {that.methodExecution('getBluetoothDevices');}});},// 开始搜寻附近的蓝牙外围设备startBluetoothDevicesDiscovery() {let that = this;// 开始搜寻附近的蓝牙外围设备wx.startBluetoothDevicesDiscovery({// 此字段会导致startBluetoothDevicesDiscovery不执行// services: ['YX'],success() {that.getBluetoothDevices();},fail() {that.methodExecution('startBluetoothDevicesDiscovery');}});},// 蓝牙开锁openBluetoothAdapter() {let that = this,thatData = that.data;if (!that.data.instructVal) return wx.showToast({title: '请输入指令',icon: 'none'});if (timeout) return wx.showToast({title: '加载中',icon: 'none'});wx.showLoading({title: '加载中',mask: true});timeout = setTimeout(() => {that.failShowToast('开锁失败');}, 1000 * 26);if (thatData.deviceId && thatData.serviceId && thatData.characteristicId) return that.writeBLECharacteristicValue();// 初始化蓝牙模块wx.openBluetoothAdapter({success() {that.setData({devices: [],deviceId: '',services: [],serviceId: '',characteristics: [],characteristicId: ''}, () => that.startBluetoothDevicesDiscovery());},fail() {that.failShowToast('查看手机蓝牙是否打开');}});},onLoad() {}
})