OpeningActivity.java 文件源码

private void startIntroTextAnimation() {
    if ( Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        Animator introAnimator = AnimatorInflater.loadAnimator(this, R.animator.intro);
        introAnimator.setTarget(introTextView);
        introAnimator.start();
    } else {
        Keyframe kf0 = Keyframe.ofFloat(0f, 0);
        Keyframe kf1 = Keyframe.ofFloat(.2f, 1);
        Keyframe kf2 = Keyframe.ofFloat(.9f, 1);
        Keyframe kf3 = Keyframe.ofFloat(1f, 0);
        PropertyValuesHolder pvh = PropertyValuesHolder.ofKeyframe("alpha", kf0, kf1, kf2, kf3);
        ObjectAnimator alphaAnimator = ObjectAnimator.ofPropertyValuesHolder(introTextView, pvh);
        alphaAnimator.setInterpolator(new DecelerateInterpolator());
        alphaAnimator.setDuration(6000).setStartDelay(1000);
        alphaAnimator.start();
    }
}