无法从另一个类访问方法

Question

我正在尝试访问另一个类的方法，因为我将类从 StatelessWidget 更改为 StatefulWidget 我无法访问 StatefulWidget 中的 addItemToList 方法，我想使用 setState，虽然我知道它只适用于 StatefulWidget 或 StatelessWidget。 这是我正在使用的代码，第一部分是我试图调用 addItemToList 的方法所在的位置：

class ScoreScreen extends StatefulWidget {
  @override
  _ScoreScreenState createState() => _ScoreScreenState();
}

class _ScoreScreenState extends State<ScoreScreen> {
  
  String _nome;

  String get nome => this._nome;

  QuestionController _qnController = Get.put(QuestionController());

  final List<String> names = <String>[
    'Aby',
    'Aish',
    'Ayan',
    'Ben',
    'Bob',
    'Charlie',
    'Cook',
    'Carline'
  ];

  final List<int> msgCount = <int>[2, 0, 10, 6, 52, 4, 0, 2];

  List<int> auxInt = <int>[];

  List<String> auxString = <String>[];

  void addItemToList() async {
    
    setState(() {
          names.insert(0, _qnController.nome);
    msgCount.insert(0, _qnController.numOfCorrectAns);
    auxInt = msgCount;
    auxString = names;
    print(names);
      
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(....

第二部分是我尝试调用该方法的地方，只是为了记住它与 StatelessWidget 一起工作，但现在我进行了更改，它不是并说 The method 'addItemToList' isn't defined for the type 'ScoreScreen'.;

// We use get package for our state management

ScoreScreen score = Get.put(ScoreScreen());

class QuestionController extends GetxController
    with SingleGetTickerProviderMixin {
  // Lets animated our progress bar

  AnimationController _animationController;
  Animation _animation;
  // so that we can access our animation outside
  Animation get animation => this._animation;

  PageController _pageController;
  PageController get pageController => this._pageController;

  List<Question> _questions = sample_data.map((question) {
    // shuffle the options
    List<String> _options = question["options"];

    //_options.shuffle();

    return Question(
        id: question['id'],
        question: question['question'],
        options: _options,
        answer: question['answer'],
        bandeira: question['bandeira']);
  }).toList()
    ..shuffle(); // remove this shuffle to check if options are shuffled

  List<Question> get questions => this._questions;

  bool _isAnswered = false;
  bool get isAnswered => this._isAnswered;

  String _correctAns;
  String get correctAns => this._correctAns;

  String _selectedAns;
  String get selectedAns => this._selectedAns;

  int _indexQ;
  int get indexQ => this._indexQ;

  // for more about obs please check documentation
  RxInt _questionNumber = 1.obs;
  RxInt get questionNumber => this._questionNumber;

  String _nome;
  String get nome => this._nome;

  int _numOfCorrectAns = 0;
  int get numOfCorrectAns => this._numOfCorrectAns;

  // called immediately after the widget is allocated memory
  @override
  void onInit() {
    // Our animation duration is 60 s
    // so our plan is to fill the progress bar within 60s
    _animationController =
        AnimationController(duration: Duration(seconds: 60), vsync: this);
    _animation = Tween<double>(begin: 0, end: 1).animate(_animationController)
      ..addListener(() {
        // update like setState
        update();
      });

    // start our animation
    // Once 30s is completed go to the next qn
    _animationController.forward().whenComplete(nextQuestion);
    _pageController = PageController();

    super.onInit();

    if (_questionNumber == _questions.length) {
      reset();
      Get.to(() => WelcomeScreen());
      _animationController.reset();
    }
  }

  // // called just before the Controller is deleted from memory
  @override
  void onClose() {
    super.onClose();
    _animationController.dispose();
    _pageController.dispose();
  }

  void checkAns(Question question, int selectedIndex, List opcoes) {
    // because once user press any option then it will run
    _isAnswered = true;
    _correctAns = question.answer;

    _selectedAns = opcoes[selectedIndex];
    int index = opcoes.indexOf(_correctAns);

    if (selectedIndex == index) _numOfCorrectAns++;

    // It will stop the counter
    _animationController.stop();
    update();

    // Once user select an ans after 2s it will go to the next qn
    Future.delayed(Duration(seconds: 1), () {
      nextQuestion();
    });
  }

  void nextQuestion() {
    if (_questionNumber.value != _questions.length) {
      _isAnswered = false;
      _pageController.nextPage(
          duration: Duration(milliseconds: 250), curve: Curves.ease);

      // Reset the counter
      _animationController.reset();

      // Then start it again
      // Once timer is finish go to the next qn
      _animationController.forward().whenComplete(nextQuestion);
    } else {
      // Get package provide us simple way to naviigate another page

      // HERE I TRY TO CALL THE METHOD, but it is not working
      ScoreScreen().addItemToList();

      Get.to(() => ScoreScreen());
    }
  }