pageview.builder ，当我点击 option

如何解决pageview.builder ，当我点击 option

我的问题页面没有跳转到下一个索引，动画播放但是当我单击选项按钮动画不会停止可能是问题动画但是当动画时间已满时出现错误位置 isnotEmpty 我该如何解决这个问题我做了所有的一部分应用程序刚刚离开此页面，我没有找到任何解决方案，如果有人知道你能帮我吗

              physics: NeverScrollableScrollPhysics(),controller: _controller.pageController,itemCount: snapshot.data.docs.length,onPageChanged: _controller.updateTheQnNum,itemBuilder: (context,index){
                return GetxPlayCard(
                  index: index,questionModel: getQuestionModelFromDataSnapshot(snapshot.data.docs[index]),);
              },);


                GestureDetector(
                onTap: () async{
                  if (!widget.questionModel.answered) {
                    if (widget.questionModel.option1 ==
                        widget.questionModel.correctOption) {
                      optionSelected = widget.questionModel.option1;
                      widget.questionModel.answered = true;
                      _correct = _correct + 1;
                      _notAttempted = _notAttempted - 1;
                      setState(() {});
                      Future.delayed(Duration(seconds: 3),() {
                       return  _controller.nextQuestion;
                      });
                    } else {
                      optionSelected = widget.questionModel.option1;
                      widget.questionModel.answered = true;
                      _incorrect = _incorrect + 1;
                      setState(() {});
                      Future.delayed(Duration(seconds: 3),() {
                       return  _controller.nextQuestion;
                      });
                    }
                  }
                },child: GetxOption(
                  corrextAnswer: widget.questionModel.correctOption,description: widget.questionModel.option1,option: 'A',optionSelected: optionSelected,),class ControllerQuestion extends GetxController
    with SingleGetTickerProviderMixin {
  AnimationController animationController;
  Animation animation;

  Animation get animationn => this.animation;

  PageController pageController;

  int total = 0;
  int _correct = 0;
  int _incorrect = 0;
  int _notAttempted = 0;
  String optionSelected = "";

  RxInt _questionNumber = 1.obs;
  RxInt get questionNumber => this._questionNumber;

  @override
  void onInit() {
    animationController =
        AnimationController(duration: Duration(seconds: 60),vsync: this);
    animation = Tween<double>(begin: 0,end: 1).animate(animationController)
      ..addListener(() {
        // update like setState
        update();
      });

    animationController.forward().then((_) {
      nextQuestion;
    });
    pageController = PageController();
    super.onInit();
  }

  @override
  void onClose() {
    super.onClose();
    animationController.dispose();
    pageController.dispose();
  }

  QuestionModel questionModel;

  BuildContext context;
  int index;

  Future<void> nextQuestion(questionnumber,indexx) async {
    if (questionnumber != indexx) {
      pageController.nextPage(
          duration: Duration(milliseconds: 200),curve: Curves.elasticIn);
      update();

      animationController.reset();
      animationController.forward().then((_) {
        nextQuestion(questionnumber,indexx);
      });
      update();
    } else {
      Navigator.pushReplacement(
          context,MaterialPageRoute(
              builder: (context) => Resultst(
                  total: total,correct: _correct,incorrect: _incorrect)));
    }
  }

  void updateTheQnNum(int index) {
    _questionNumber.value = index + 1;
    update();
  }
}