UserView.dart

class UserView extends StatefulWidget {
  const UserView({Key? key}) : super(key: key);
  
    @override
  State<UserViewState> createState() => _UserViewState();
}

class _UserViewState extends State<UserViewState> {
  var _token = "";
  static const channelName = 'com.myflutterapp/data';
  final methodChannel = MethodChannel(channelName);

  initStuff() async {
    _token = await methodChannel.invokeMethod('getUserToken');
    setState(() {});
  }

  @override
  void initState() {
    super.initState();
    initStuff();
    print(_token); // 
  }
}