如何在使用 Animator 加载期间淡入淡出文本？

Question

我想在我的应用程序加载过程中淡入和淡出一些文本。 首先，我在一个带有计数器的循环中尝试了这个，但它不起作用。 我试过这个：

        int i = 0;
        for(i=0; i < 5; i++){
            batteryAnimator = ObjectAnimator.ofFloat(tvBattery, "alpha", 1).setDuration(600);
            batteryAnimator.setStartDelay(200);
            batteryAnimator.start();
            screenAnimator = ObjectAnimator.ofFloat(tvScreen, "alpha", 1).setDuration(600);
            screenAnimator.setStartDelay(1500);
            screenAnimator.start();
            sensorAnimator = ObjectAnimator.ofFloat(tvSensor, "alpha", 1).setDuration(600);
            sensorAnimator.setStartDelay(3000);
            sensorAnimator.start();
            wifiAnimator = ObjectAnimator.ofFloat(tvWifi, "alpha", 1).setDuration(600);
            wifiAnimator.setStartDelay(4500);
            wifiAnimator.start();


            batteryAnimator = ObjectAnimator.ofFloat(tvBattery, "alpha", 0).setDuration(600);
            batteryAnimator.setStartDelay(6000);
            batteryAnimator.start();
            screenAnimator = ObjectAnimator.ofFloat(tvScreen, "alpha", 0).setDuration(600);
            screenAnimator.setStartDelay(6000);
            screenAnimator.start();
            sensorAnimator = ObjectAnimator.ofFloat(tvSensor, "alpha", 0).setDuration(600);
            sensorAnimator.setStartDelay(6000);
            sensorAnimator.start();
            wifiAnimator = ObjectAnimator.ofFloat(tvWifi, "alpha", 0).setDuration(600);
            wifiAnimator.setStartDelay(6000);
            wifiAnimator.start();
    }

我尝试使用batteryAnimator.setRepeatedMode(ValueAnimator.RESTART) 和battery.Animator.setRepeatCount(ValueAnimator.INFINITE)，我想我必须使用这样的东西，但文本像圣诞树一样闪烁..

如果有人可以帮助我..

Answer 1

创建此方法。这将使您的视图（在您的情况下，您的TextView）淡入淡出：

    public void fadeInAndOut(final View view) {
        ObjectAnimator fadeOut = ObjectAnimator.ofFloat(view, "alpha", 0f);
        fadeOut.setDuration(500);
        fadeOut.setInterpolator(new DecelerateInterpolator());

        ObjectAnimator fadeIn = ObjectAnimator.ofFloat(view, "alpha", 1f);
        fadeIn.setDuration(500);
        fadeIn.setInterpolator(new DecelerateInterpolator());

        AnimatorSet set = new AnimatorSet();
        set.play(fadeIn).after(fadeOut);

        set.start();
    }

然后，你需要在一些间隔之间调用这个函数。例如，我使用的是CountDownTimer。它将以 1 秒的间隔被调用 20 次。

new CountDownTimer(20000, 1000) {

    public void onTick(long millisUntilFinished) {
      //This will be called every time timer ticks
      fadeInAndOut(/*your TextView goes here*/)
    }

    public void onFinish() {
       //Timer is done. 
    }

}.start();