为什么我的后退按钮不起作用

Question

我想使用navCtrl.push将后退按钮从 exercisesPage 推送到 exerciseFlashCardPage 。由于某种原因，页面重定向到page2并具有后退按钮，但是该按钮不起作用甚至无法单击。

export class ExerciseFlashcardPage {
  currentQuestion = 0;
  exercise: Exercise[] = [];
  questions: Observable<any>;
  type: string;
  answer = {} as Answer;
  mssg = {} as AnswerMssg;
  isValid = false;
  constructor(public navCtrl: NavController, public navParams: NavParams, public afd: AngularFireDatabase,private cdRef:ChangeDetectorRef) {
    this.type = this.navParams.get('data');
    this.questions = this.afd.list('exercises/' + this.type).valueChanges();
  }
  ionViewDidLoad() {
    console.log('ionViewDidLoad ExerciseFlashcardPage');
  }
  next(){
    this.isValid= false;
    ++this.currentQuestion;
  }
  check(ans : any){
    this.isValid = true;
    if(this.answer.answered ==ans){
      this.mssg.status = "Correct"
      this.mssg.answer = ans;
      this.mssg.icon = "checkmark-circle-outline";
    }    
    else{
      this.mssg.status = "Wrong"
      this.mssg.answer = ans ;
      this.mssg.icon = "close-circle-outline";
    }
  }

}

export class ExercisesPage {
  constructor(public navCtrl: NavController, public navParams: NavParams) {}
  public navigateTo(text:string){
    this.navCtrl.push("ExerciseFlashcardPage", {
      data:text,
    });
  }

}

Answer 1

请检查控制台并在此处共享该信息。
通常，当某些操作不起作用时，是因为存在一些控制台错误。