uniapp 蓝牙数据交互demo代码

以下是一个简单的UniApp蓝牙数据交互demo代码，仅供参考：

<template>
  <div>
    <button @click="sendMsg">发送消息</button>
    <button @click="receiveMsg">接收消息</button>
    <textarea v-model="msg"></textarea>
  </div>
</template>

<script>
export default {
  data() {
    return {
      msg: '', // 发送的消息
      connectedDeviceId: '', // 已连接设备Id
      serviceId: '', // 服务Id
      characteristicId: '', // 特征值Id
    }
  },
  methods: {
    // 发送消息
    sendMsg() {
      uni.writeBLECharacteristicValue({
        deviceId: this.connectedDeviceId,
        serviceId: this.serviceId,
        characteristicId: this.characteristicId,
        value: this.msg,
        success: res => {
          console.log(res)
        },
        fail: err => {
          console.error(err)
        }
      })
    },
    // 接收消息
    receiveMsg() {
      uni.onBLECharacteristicValueChange(res => {
        console.log(res)
        console.log(this.ab2str(res.value))
      })
      uni.notifyBLECharacteristicValueChanged({
        state: true,
        deviceId: this.connectedDeviceId,
        serviceId: this.serviceId,
        characteristicId: this.characteristicId,
        success: res => {
          console.log(res)
        },
        fail: err => {
          console.error(err)
        }
      })
    },
    // ArrayBuffer转字符串
    ab2str(buf) {
      return String.fromCharCode.apply(null, new Uint8Array(buf))
    },
  },
  onShow() {
    // 获取已连接设备Id、服务Id、特征值Id等信息
    uni.getConnectedBluetoothDevices({
      success: res => {
        console.log(res)
        this.connectedDeviceId = res.devices[0].deviceId
        uni.getBLEDeviceServices({
          deviceId: this.connectedDeviceId,
          success: res => {
            console.log(res)
            this.serviceId = res.services[0].uuid
            uni.getBLEDeviceCharacteristics({
              deviceId: this.connectedDeviceId,
              serviceId: this.serviceId,
              success: res => {
                console.log(res)
                this.characteristicId = res.characteristics[0].uuid
              },
              fail: err => {
                console.error(err)
              }
            })
          },
          fail: err => {
            console.error(err)
          }
        })
      },
      fail: err => {
        console.error(err)
      }
    })
  },
}
</script>

以上代码实现了基本的蓝牙数据发送、接收等功能，但仅仅是一个demo，实际使用时需要根据具体需求进行修改。需要注意的是，蓝牙操作涉及到很多异步回调，需要仔细处理回调的顺序和逻辑。