微信小程序蓝牙API使用demo教程完整版

原创 dujingya 随笔 小程序 60阅读 23 天前 举报

github地址:https://github.com/dujingya/blueDevice/blob/master/blueDevice.md

使用mpvue 开发小程序过程中 简单介绍一下微信小程序蓝牙连接过程 #在蓝牙连接的过程中部分api需要加定时器延时1秒到2秒左右再执行,原因为何不知道,小程序有这样的要求 #1.首先是要初始化蓝牙:openBluetoothAdapter()

if (wx.openBluetoothAdapter) {
wx.openBluetoothAdapter({
success: function(res) {
/ 获取本机的蓝牙状态 /
setTimeout(() => {
getBluetoothAdapterState()
}, 1000)
},
fail: function(err) {
// 初始化失败
}
})
} else {

}

2.检测本机蓝牙是否可用:

要在上述的初始化蓝牙成功之后回调里调用
getBluetoothAdapterState() {
var that = this;
that.toastTitle = '检查蓝牙状态'
wx.getBluetoothAdapterState({
success: function(res) {
startBluetoothDevicesDiscovery()
},
fail(res) {
console.log(res)
}
})
}

3. 开始搜索蓝牙设备:

startBluetoothDevicesDiscovery() {
var that = this;
setTimeout(() => {
wx.startBluetoothDevicesDiscovery({
success: function(res) {
/ 获取蓝牙设备列表 /
that.getBluetoothDevices()
},
fail(res) {
}
})
}, 1000)
}

4. 获取搜索到的蓝牙设备列表

/ that.deviceName 是获取到的蓝牙设备的名称, 因为蓝牙设备在安卓和苹果手机上搜到的蓝牙地址显示是不一样的,所以根据设备名称匹配蓝牙/
getBluetoothDevices() {
var that = this;
setTimeout(() => {
wx.getBluetoothDevices({
services: [],
allowDuplicatesKey: false,
interval: 0,
success: function(res) {
if (res.devices.length > 0) {
if (JSON.stringify(res.devices).indexOf(that.deviceName) !== -1) {
for (let i = 0; i < res.devices.length; i++) {
if (that.deviceName === res.devices[i].name) {
/ 根据指定的蓝牙设备名称匹配到deviceId /
that.deviceId = that.devices[i].deviceId;
setTimeout(() => {
that.connectTO();
}, 2000);
};
};
} else {
}
} else {
}
},
fail(res) {
console.log(res, '获取蓝牙设备列表失败=====')
}
})
}, 2000)
},

5.连接蓝牙

匹配到的蓝牙设备ID 发送连接蓝牙的请求, 连接成功之后 应该断开蓝牙搜索的api,然后去获取所连接蓝牙设备的service服务
connectTO() {
wx.createBLEConnection({
deviceId: deviceId,
success: function(res) {
that.connectedDeviceId = deviceId;
/ 4.获取连接设备的service服务 /
that.getBLEDeviceServices();
wx.stopBluetoothDevicesDiscovery({
success: function(res) {
console.log(res, '停止搜索')
},
fail(res) {
}
})
},
fail: function(res) {
}
})
}

6. 获取蓝牙设备的service服务,获取的serviceId有多个要试着连接最终确定哪个是稳定版本的service 获取服务完后获取设备特征值

getBLEDeviceServices() {
setTimeout(() => {
wx.getBLEDeviceServices({
deviceId: that.connectedDeviceId,
success: function(res) {
that.services = res.services
/ 获取连接设备的所有特征值 /
that.getBLEDeviceCharacteristics()
},
fail: (res) => {
}
})
}, 2000)
},

7.获取蓝牙设备特征值

获取到的特征值有多个,最后要用的事能读,能写,能监听的那个值的uuid作为特征值id,
getBLEDeviceCharacteristics() {
setTimeout(() => {
wx.getBLEDeviceCharacteristics({
deviceId: connectedDeviceId,
serviceId: services[2].uuid,
success: function(res) {
for (var i = 0; i < res.characteristics.length; i++) {
if ((res.characteristics[i].properties.notify || res.characteristics[i].properties.indicate) &&
(res.characteristics[i].properties.read && res.characteristics[i].properties.write)) {
console.log(res.characteristics[i].uuid, '蓝牙特征值 ==========')
/ 获取蓝牙特征值 /
that.notifyCharacteristicsId = res.characteristics[i].uuid
// 启用低功耗蓝牙设备特征值变化时的 notify 功能
that.notifyBLECharacteristicValueChange()
}
}
},
fail: function(res) {
}
})
}, 1000)
},

8.启动notify 蓝牙监听功能 然后使用 wx.onBLECharacteristicValueChange用来监听蓝牙设备传递数据 #接收到的数据和发送的数据必须是二级制数据, 页面展示的时候需要进行转换

    notifyBLECharacteristicValueChange() { // 启用低功耗蓝牙设备特征值变化时的 notify 功能
        var that = this;
        console.log('6.启用低功耗蓝牙设备特征值变化时的 notify 功能')
        wx.notifyBLECharacteristicValueChange({
            state: true,
            deviceId: that.connectedDeviceId,
            serviceId: that.notifyServicweId,
            characteristicId: that.notifyCharacteristicsId,
            complete(res) {
                /*用来监听手机蓝牙设备的数据变化*/
                wx.onBLECharacteristicValueChange(function(res) {
                    /**/
                    that.balanceData += that.buf2string(res.value)
                    that.hexstr += that.receiveData(res.value)
                })
            },
            fail(res) {
                console.log(res, '启用低功耗蓝牙设备监听失败')
                that.measuringTip(res)
            }
        })
    },

    /*转换成需要的格式*/
     buf2string(buffer) {
                var arr = Array.prototype.map.call(new Uint8Array(buffer), x => x)
                return arr.map((char, i) => {
                    return String.fromCharCode(char);
                }).join('');
    },
      receiveData(buf) {
                return this.hexCharCodeToStr(this.ab2hex(buf))
      },
      /*转成二进制*/
       ab2hex (buffer) {
          var hexArr = Array.prototype.map.call(
              new Uint8Array(buffer), function (bit) {
                  return ('00' + bit.toString(16)).slice(-2)
              }
          )
          return hexArr.join('')
      },
      /*转成可展会的文字*/
      hexCharCodeToStr(hexCharCodeStr) {
          var trimedStr = hexCharCodeStr.trim();
          var rawStr = trimedStr.substr(0, 2).toLowerCase() === '0x' ? trimedStr.substr(2) : trimedStr;
          var len = rawStr.length;
          var curCharCode;
          var resultStr = [];
          for (var i = 0; i < len; i = i + 2) {
              curCharCode = parseInt(rawStr.substr(i, 2), 16);
              resultStr.push(String.fromCharCode(curCharCode));
          }
          return resultStr.join('');
      },

向蓝牙设备发送数据
sendData(str) {
let that = this;
let dataBuffer = new ArrayBuffer(str.length)
let dataView = new DataView(dataBuffer)
for (var i = 0; i < str.length; i++) {
dataView.setUint8(i, str.charAt(i).charCodeAt())
}
let dataHex = that.ab2hex(dataBuffer);
this.writeDatas = that.hexCharCodeToStr(dataHex);
wx.writeBLECharacteristicValue({
deviceId: that.connectedDeviceId,
serviceId: that.notifyServicweId,
characteristicId: that.notifyCharacteristicsId,
value: dataBuffer,
success: function (res) {
console.log('发送的数据:' + that.writeDatas)
console.log('message发送成功')
},
fail: function (res) {
},
complete: function (res) {
}
})
},
当不需要连接蓝牙了后就要关闭蓝牙,并关闭蓝牙模块
// 断开设备连接
closeConnect() {
if (that.connectedDeviceId) {
wx.closeBLEConnection({
deviceId: that.connectedDeviceId,
success: function(res) {
that.closeBluetoothAdapter()
},
fail(res) {
}
})
} else {
that.closeBluetoothAdapter()
}
},
// 关闭蓝牙模块
closeBluetoothAdapter() {
wx.closeBluetoothAdapter({
success: function(res) {
},
fail: function(err) {
}
})
},

评论 ( 0 )
最新评论
暂无评论

赶紧努力消灭 0 回复