Android 动画不显示-为什么？

我是新来的，正在网上学习。这是我第一次在安卓学习动画。问题是，当我选择答案时，我的卡片视图动画应该立即显示。但我一点击它就没显示出来。但我发现，在我点击按钮后，我需要按下Home按钮，然后从后台应用程序中恢复它来启动动画。动画只有在我完成此过程后才会启动。吐司没有问题。在我选择答案后，我总是需要这样做来显示我的动画。这个应用程序是真是假。 另外，编码与我的在线教程完全相同。也许我的电话有问题？？我使用的是三星S 7 edge

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private TextView QuestionTextView,QcountTextView;
    private Button Tbutton,Fbutton;
    private ImageButton prev,next;
    private int count = 0;
    private CardView cardView;
    private Animation shake;
    public Questions Qarray[] = new Questions[]{
            new Questions(R.string.Q1, true),
            new Questions(R.string.Q2, false),
            new Questions(R.string.Q3, true),
            new Questions(R.string.Q4, true),
            new Questions(R.string.Q5, false),
            new Questions(R.string.Q6, true),
            new Questions(R.string.Q7, false)
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Tbutton = findViewById(R.id.tb);
        Fbutton = findViewById(R.id.fb);
        QuestionTextView = findViewById(R.id.questionshow);
        QcountTextView = findViewById(R.id.Qcount);
        next = findViewById(R.id.nb);
        prev = findViewById(R.id.pb);
        cardView = findViewById(R.id.cardView);
        shake = AnimationUtils.loadAnimation(MainActivity.this,R.anim.shakeanimation);

        Tbutton.setOnClickListener(this);
        Fbutton.setOnClickListener(this);
        next.setOnClickListener(this);
        prev.setOnClickListener(this);

        QuestionTextView.setText(Qarray[count].question);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.tb:
                giveanswer(true);
                pagechange();
                break;
            case R.id.fb:
                giveanswer(false);
                pagechange();
                break;
            case R.id.pb:
                if(count != 0) {
                    count = (count - 1);
                    pagechange();
                }
                break;
            case R.id.nb:
                count = (count + 1) % Qarray.length;
                pagechange();
                break;

        }
    }

    private void pagechange() {
        QuestionTextView.setText(Qarray[count].getQuestion());
        QcountTextView.setText((count+1) + " out of " + Qarray.length);
    }

    private void giveanswer(boolean b) {
        boolean correctanswer = Qarray[count].ans;
        if(b == correctanswer){
            fadeView();
            Toast.makeText(this,R.string.yes,Toast.LENGTH_SHORT).show();
        }
        else{
            ShakeAnimation();
            Toast.makeText(this,R.string.no,Toast.LENGTH_SHORT).show();
        }
    }

    private  void fadeView(){
        AlphaAnimation alphaAnimation = new AlphaAnimation(1.0f,0.0f);
        alphaAnimation.setDuration(350);
        alphaAnimation.setRepeatCount(1);
        alphaAnimation.setRepeatMode(Animation.REVERSE);
        cardView.setAnimation(alphaAnimation);

        alphaAnimation.setAnimationListener(new 
    Animation.AnimationListener() {
            @Override
            public void onAnimationStart(Animation animation) {
                cardView.setCardBackgroundColor(Color.GREEN);
            }

            @Override
                    public void onAnimationEnd(Animation animation){
                cardView.setCardBackgroundColor(Color.rgb(41,226,205));
            }

            @Override
            public void onAnimationRepeat(Animation animation) {

            }
        });
    }

    private void ShakeAnimation(){
        cardView.setAnimation(shake);
        shake.setAnimationListener(new Animation.AnimationListener() {
            @Override
            public void onAnimationStart(Animation animation) {
                cardView.setCardBackgroundColor(Color.RED);
            }

            @Override
            public void onAnimationEnd(Animation animation) {
                cardView.setCardBackgroundColor(Color.rgb(41,226,205));
            }

            @Override
            public void onAnimationRepeat(Animation animation) {

            }
        });
    }
}

---

我希望在选择答案后立即显示动画。

您需要调用

alphaAnimation.start（）或
抖动.start（）只有动画侦听器并不能在您希望动画启动时启动动画

尝试将这些线添加到希望动画运行的位置

例如：

AlphaAnimation alphaAnimation = new AlphaAnimation(1.0f,0.0f);
    alphaAnimation.setDuration(350);
    alphaAnimation.setRepeatCount(1);
    alphaAnimation.setRepeatMode(Animation.REVERSE);
    cardView.setAnimation(alphaAnimation);
    alphaAnimation.start();

如果我没有弄错的话，
setAnimation
应该与xml动画一起使用
您忘了给StartHanks打电话了。我把它改成了cardView.startAnimation（震动）；成功了。