disconnect method Null safety

Future<void> disconnect()
override

Disconnect from the hub.

Implementation

Future<void> disconnect() async {
  print("Disconnecting... $_service, $_characteristic");

  _subscription?.cancel();
  _subscription = null;

  if (_service != null || _characteristic != null) {
    _service = null;
    _characteristic = null;
    await device.disconnect();
    print("Disconnected");
  }
}