Код-ревью: работа с платформенным каналом

class Scanner {
  final _channel = MethodChannel('scanner');
  final _events = EventChannel('scanner/events');

  Future<String> scan() async {
    final code = await _channel.invokeMethod('scan');
    return code;
  }

  void listen(void Function(String) onCode) {
    _events.receiveBroadcastStream().listen((e) => onCode(e));
  }

  Future<void> setUser(User user) =>
      _channel.invokeMethod('setUser', user);
}