Flutter Blue Read 特性返回错误

Question

我只想读取我的服务特征的值。但我收到了这个错误： [[错误：flutter/lib/ui/ui_dart_state.cc(148)]

未处理的异常：PlatformException(read_characteristic_error, unknown reason, if readCharacteristic is called before last read finished., null)]

1

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

知道这里发生了什么吗？ 谢谢！！

Answer 1

1. 我会确保您的 GATT 服务正在通过您的服务具有所有唯一的 UUID。

2. 我会试一下下面的代码。到目前为止，我已经使用 Flutter Blue 完成了十几个应用程序，我看到的唯一问题是与读取和响应有关。

   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();
   }