Problems with read subscription

Before starting this I want to shortly mention two things. Thanks for creating and maintaining this library and I’m pretty sure the fault is on my side. I just don’t know what I’m doing wrong 🙈

Mobile Device Environment

• Device: Android
• OS: API 29

Application Environment Provide information about your development environment:

• React Native version: 0.63.4
• RN Bluetooth Classic version: 1.60.0-rc.17

Describe the bug I have an app that can connect to python client on a laptop and send messages but does only receives the messages from the python client once the connection is closed. Additionally I get a weird error when I try to remove the read subscription. I’m not sure if both problems are related.

Below you can find the two important files. When I run readSubscription.remove() I receive the following error: Cannot read from DEVICE_READ, not currently connected

bluetooth.js

const onDeviceDisconnect = async (
  device,
  readSubscription,
  dispatch,
  changeDeviceConnectionStatus,
) => {
  readSubscription.remove()

  changeDeviceConnectionStatus('disconnected')
  dispatch(setDevice({ device: null }))

  console.log('disconnected device: ' + device.name)
}

export const sendMessageToDevice = async (device, msg) => {
  const msgStr = createBluetoothMessage(msg)

  try {
    await RNBluetoothClassic.writeToDevice(device.address, msgStr)
  } catch (error) {
    console.error('error reply message' + msgStr)
  }
}

export const connectBluetoothDevice = async (
  device,
  dispatch,
  changeDeviceConnectionStatus,
  onDataReceived,
) => {
  try {
    changeDeviceConnectionStatus('connecting')
    let connection = await device.isConnected()

    // check if already connected
    if (!connection) {
      connection = await device.connect({
        DELIMITER: Config.BLUETOOTH_DELIMITER,
      })
    }

    changeDeviceConnectionStatus('connected')

    let readSubscription = device.onDataReceived(data => onDataReceived(data))

    RNBluetoothClassic.onDeviceDisconnected(device =>
      onDeviceDisconnect(
        device,
        readSubscription,
        dispatch,
        changeDeviceConnectionStatus,
      ),
    )
  } catch (error) {
    console.error(error)
    changeDeviceConnectionStatus('connection failed')
    dispatch(setDevice({ device: null }))
  }
}

Screen.js

const ExampleContainer = () => {
  const device = useSelector(store => store.bluetooth.device)
  const [connectionStatus, setConnectionStatus] = useState('not connected')
  const dispatch = useDispatch()

  async function onDataReceived(data) {
    await data
    console.log(data)
  }

  async function onSendCommmand(command) {
    await sendMessageToDevice(device, { type: 'command', command: command })
  }

  useEffect(() => {
    async function connectDevice(device) {
      await connectBluetoothDevice(
        device,
        dispatch,
        setConnectionStatus,
        onDataReceived,
      )
    }

    if (device !== null) {
      connectDevice(device)
    }
  }, [device, dispatch])

  return (...)
  }
}

export default ExampleContainer

[brunovollmer]

So the problem was related to specific kind of message we send.

[kenjdavidson]

Right on man, I’m glad you’ve got it up and going!