wx.onBLECharacteristicValueChange(function callback)

基础库 1.1.0 开始支持，低版本需做兼容处理。

监听低功耗蓝牙设备的特征值变化事件。必须先启用 notifyBLECharacteristicValueChange 接口才能接收到设备推送的 notification。

参数

function callback

低功耗蓝牙设备的特征值变化事件的回调函数

参数

Object res

lanyatest.wxml代码：

<!--pages/lanyatest/lanyatest.wxml-->
<view class="contentview">
  <view  class='myview' >
      {
   {info}}
  </view>
  <button type="primary" class="button" bindtap="lanyatest1">1初始化蓝牙</button>
  <button type="primary" class="button" bindtap="lanyatest2">2获取蓝牙状态</button>
  <button type="primary" class="button" bindtap="lanyatest3">3搜索周边设备</button>
  <button type="primary" class="button" bindtap="lanyatest4">4获取所有设备</button>
  <block wx:for="{
   {devices}}" wx:key="{
   {test}}">
    <button type="primary" class="button" id="{
   {item.deviceId}}" style='background-color:red' bindtap="lanyaconnect">5连接{
   {item.name}}         </button>
  </block>
  <button type="primary" class="button" bindtap="lanyatest6">6停止搜索周边蓝牙设备</button>
  <button type="primary" class="button" bindtap="lanyatest7">7获取所有service</button>
  <button type="primary" class="button" bindtap="lanyatest8">8获取所有特征值</button>
  <button type="primary" class="button" bindtap="lanyatest9">9启用特征值变化notify</button>
  <button type="primary" class="button" bindtap="lanyatest10">10接收蓝牙返回消息</button>
</view>

lanyatest.js代码：

// pages/lanyatest/lanyatest.js
Page({
  /**
   * 页面的初始数据
   */
  data: {
    info:"未初始化蓝牙适配器",
    connectedDeviceId:"",
    deviceId:"",
    services:"",
    servicesUUID:"0000ff00-0000-1000-8000-00805f9b34fb",
    serviceId:"",
    notifyCharacteristicsId:"",
    writeCharacteristicsId: "",
  },
  lanyatest1(event){
    var that = this;
    wx.openBluetoothAdapter({
      success: function (res) {
        console.log('初始化蓝牙适配器成功')
        //页面日志显示
        that.setData({
          info: '初始化蓝牙适配器成功'
        })
      },
      fail: function (res) {
        console.log('请打开蓝牙和定位功能')
        that.setData({
          info: '请打开蓝牙和定位功能'
        })
      }
    })
  },
  lanyatest2(event){
    var that = this;
    wx.getBluetoothAdapterState({
      success: function (res) {
        //打印相关信息
        console.log(JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available);
        that.setData({
          info: JSON.stringify(res.errMsg) +"\n蓝牙是否可用：" + res.available
        })
      },
      fail: function (res) {
        //打印相关信息
        console.log(JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available);
        that.setData({
          info: JSON.stringify(res.errMsg) + "\n蓝牙是否可用：" + res.available
        })
      }
    })
  },
  lanyatest3(event){
    var that = this;
    wx.startBluetoothDevicesDiscovery({
      services: ['FEE7'], //如果填写了此UUID，那么只会搜索出含有这个UUID的设备，建议一开始先不填写或者注释掉这一句
      success: function (res) {
        that.setData({
          info: "搜索设备" + JSON.stringify(res),
        })
        console.log('搜索设备返回' + JSON.stringify(res))
      }
    })
  },
  lanyatest4(event){
    var that = this;
    wx.getBluetoothDevices({
      success: function (res) {
        that.setData({
          info: "设备列表\n" + JSON.stringify(res.devices),
          devices: res.devices
        })
        console.log('搜设备数目：' + res.devices.length)
        console.log('设备信息：\n' + JSON.stringify(res.devices)+"\n")
      }
    })
  },
  lanyaconnect(event){
    var that = this;
    wx.createBLEConnection({
      deviceId: event.currentTarget.id,
      success: function (res) {
        console.log('调试信息：' + res.errMsg);
        that.setData({
          connectedDeviceId: event.currentTarget.id,
          info: "MAC地址：" + event.currentTarget.id  + '  调试信息：' + res.errMsg,
        })
      },
      fail: function () {
        console.log("连接失败");
      },
    })
  },
  lanyatest6(event){
    var that = this;
    wx.stopBluetoothDevicesDiscovery({
      success: function (res) {
        console.log("停止搜索" + JSON.stringify(res.errMsg));
        that.setData({
          info: "停止搜索"  + JSON.stringify(res.errMsg),
        })
      }
    })
  },
  lanyatest7(event){
    var that = this;
    wx.getBLEDeviceServices({
      // 这里的 deviceId 需要在上面的 getBluetoothDevices 或 onBluetoothDeviceFound 接口中获取
      deviceId: that.data.connectedDeviceId,
      success: function (res) {
        console.log('services UUID:\n', JSON.stringify(res.services));
        for (var i = 0; i < res.services.length; i++) {
          console.log("第"+(i+1) + "个UUID:" + res.services[i].uuid+"\n")
        }
        that.setData({
          services: res.services,
          info: JSON.stringify(res.services),
        })
      }
    })
  },
  lanyatest8(event){
    var that = this;
    var myUUID = that.data.servicesUUID;//具有写、通知属性的服务uuid
    console.log('UUID' + myUUID)
    wx.getBLEDeviceCharacteristics({
      // 这里的 deviceId 需要在上面的接口中获取
      deviceId: that.data.connectedDeviceId,
      // 这里的 serviceId 需要在上面的 接口中获取
      serviceId: myUUID,
      success: function (res) {
        console.log("%c getBLEDeviceCharacteristics", "color:red;");
        for (var i = 0; i < res.characteristics.length; i++) {
          console.log('特征值：' + res.characteristics[i].uuid)
          if (res.characteristics[i].properties.notify) {
            console.log("notifyServicweId：", myUUID);
            console.log("notifyCharacteristicsId：", res.characteristics[i].uuid);
            that.setData({
              notifyServicweId: myUUID,
              notifyCharacteristicsId: "0000ff01-0000-1000-8000-00805f9b34fb",//手动设置notifyCharacteristicsId为这个UUID，为了方便写死在这里
            })
          }
          if (res.characteristics[i].properties.write) {
            console.log("writeServicweId：", myUUID);
            console.log("writeCharacteristicsId：", res.characteristics[i].uuid);
            that.setData({
              writeServicweId: myUUID,
              //writeCharacteristicsId: res.characteristics[i].uuid,
              writeCharacteristicsId: "0000ff02-0000-1000-8000-00805f9b34fb",//手动设置writeCharacteristicsId为这个UUID，为了方便写死在这里
            })
          }
        }
        console.log('device getBLEDeviceCharacteristics:', res.characteristics);
        that.setData({
          msg: JSON.stringify(res.characteristics),
        })
      },
      fail: function () {
        console.log("fail");
      },
    })
  },
  lanyatest9(event){
    var that = this;
    var notifyServicweId = that.data.servicesUUID;  //具有写、通知属性的服务uuid
    var notifyCharacteristicsId = that.data.notifyCharacteristicsId;
    console.log("启用notify的serviceId", notifyServicweId);
    console.log("启用notify的notifyCharacteristicsId", notifyCharacteristicsId);
    wx.notifyBLECharacteristicValueChange({
      state: true, // 启用 notify 功能
      deviceId: that.data.connectedDeviceId,
      // 这里的 serviceId 就是that.data.servicesUUID
      serviceId: notifyServicweId,
      characteristicId: that.data.notifyCharacteristicsId,
      success: function (res) {
        console.log('notifyBLECharacteristicValueChange success', res.errMsg)
        var msg = '启动notify:' + res.errMsg
        that.setData({
          info: msg
        })
      },
      fail: function () {
        console.log('启动notify:' + res.errMsg);
      },
    })
  },
  lanyatest10(event){
    var that = this;
    console.log("开始接收数据");
    wx.onBLECharacteristicValueChange(function (res) {
      console.log("characteristicId：" + res.characteristicId)
      console.log("serviceId:" + res.serviceId)
      console.log("deviceId" + res.deviceId)
      console.log("Length:" + res.value.byteLength)
      console.log("hexvalue:" + ab2hex(res.value))
      that.setData({
        info: that.data.info + ab2hex(res.value)
      })
    })
  },
//我删除了自动生成的生命周期函数
})
// ArrayBuffer转16进度字符串示例
function ab2hex(buffer) {
  var hexArr = Array.prototype.map.call(
    new Uint8Array(buffer),
    function (bit) {
      return ('00' + bit.toString(16)).slice(-2)
    }
  )
  return hexArr.join(',');
}

lanyatest.wxss代码：

/* pages/lanyatest/lanyatest.wxss */
.vertical{
  display: flex;
  flex-direction: column;
}
/**index.wxss**/
.horizontal{
  display: flex;
  flex-direction: row;
}
.btinfo{
  height:100px;
}
.contentview {
margin: 0 10px;
}
.button {
margin: 5px;
}
.myview{
  height:200px;
  word-break:break-all;/* 自动换行 */
}

真机调试结果：

打开串口调试助手愉快地发消息了