Flutter_blue: Example App crashes on write to a characteristic

Created on 7 Jun 2018 · 4Comments · Source: pauldemarco/flutter_blue

Example app in the library crashes when I try to write a value.

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ssaylanc

Most helpful comment

I have the same problem, using example app, if I tap the writeCharacteristic too quickly, it'll crash. => PlatformException(write_characteristic_error, writeCharacteristic failed, null) in messsage_codecs.dart , decodeEnvlope method.

I also write a test app, after call discoverServices and found the right service, writeCharacteristic immediately will cause the same error.

      _characteristic = _service.characteristics.first;

      _device.setNotifyValue(_characteristic, true);

      _valueChangedSubscription = _device
          .onValueChanged(_characteristic)
          .listen((d) => _handleRxData(d));

     // await Future.delayed(const Duration(milliseconds: 100));

     _device.writeCharacteristic(_characteristic, _writeCmd);

Uncomment the Future.delayed line, it works without error

RyanYANG52 on 1 Nov 2018

👍5

All 4 comments

Can you please share the log of the crash?

pauldemarco on 10 Aug 2018

Going to close this until further information is provided.

pauldemarco on 9 Oct 2018

I also write a test app, after call discoverServices and found the right service, writeCharacteristic immediately will cause the same error.

      _characteristic = _service.characteristics.first;

      _device.setNotifyValue(_characteristic, true);

      _valueChangedSubscription = _device
          .onValueChanged(_characteristic)
          .listen((d) => _handleRxData(d));

     // await Future.delayed(const Duration(milliseconds: 100));

     _device.writeCharacteristic(_characteristic, _writeCmd);

Uncomment the Future.delayed line, it works without error

RyanYANG52 on 1 Nov 2018

👍5

Is any update here?