Question

我只想阅读服务特征的值。但我收到此错误： [[ERROR：flutter / lib / ui / ui_dart_state.cc（148）]

未处理的异常：PlatformException（read_characteristic_error，未知原因，如果在上一次读取完成之前调用readCharacteristic，则可能会发生。）

我的代码：

 discoverServices() async {
     List<BluetoothService services = await device.discoverServices();
     services.forEach((service) async {
       // do something with service
       if (service.uuid.toString() == SERVICE_UUID) {
         var characteristics = await service.characteristics;
         for(BluetoothCharacteristic c in characteristics) {
           //if (characteristic.uuid.toString() == CHARACTERISTIC_UUID) {
             targetCharacteristic = c;
             List<int value = await c.read();
             print(value);
           //}
         };
       }
     });   }

code

对这里发生的事情有任何想法吗？谢谢！

Answer 1

我将确保正在通过您的服务的GATT服务具有所有唯一的UUIDS。

我会在下面给出代码。目前，我已经用Flutter Blue完成了许多应用程序，而我所看到的唯一问题就是阅读和响应。

discoverServices() async {
  List<BluetoothService> services;
  BluetoothService myImportantService;
  List<BluetoothCharacteristic> characteristics;
  BluetoothCharacteristic myImportantCharacteristic;

  //Get your services from your device.
  services = await device.discoverServices();

  //Find the service we are looking for.
  for(BluetoothService s in services) {
    //Would recommend to convert all to lowercase if comparing.
    if(s.uuid.toString().toLowerCase() == SERVICE_UUID)
      myImportantService = s;
  }

  //Get this services characteristics.
  characteristics = myImportantService.characteristics;

  //Find the characteristic we are looking for.
  for(BluetoothCharacteristic c in characteristics) {
    //Would recommend to convert all to lowercase if comparing.
    if(c.uuid.toString().toLowerCase() == CHARACTERISTIC_UUID)
      myImportantCharacteristic = c;
  }

  List<int> data = await myImportantCharacteristic.read();
}

Flutter Blue Read特性返回错误

1 个答案: