android - 如何在android中以编程方式为 View 设置动画？

Question

我正在为应用程序制作动画教程。我在 Activity 上使用 fragment 来显示 ImageView 滑动效果。我正在使用翻译动画将 ImageView 移动到特定 View 以描述其工作，但实际上我想为 ImageView 设置动画以在到达 View 后移动无限次。

Answer 1

假设 View v 是动画

    public void ViewExapand(View v)
        {
                        v.setVisibility(View.VISIBLE);

                        final int widthSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
                        final int heightSpec = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
                        v.measure(widthSpec, heightSpec);
                        ValueAnimator mAnimator = slideAnimator(0, v.getMeasuredHeight(),v);
                        mAnimator.start();
        }



private ValueAnimator slideAnimator(int start, int end, final View v)
    {
        ValueAnimator animator = ValueAnimator.ofInt(start, end);
        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                //Update Height
                int value = (Integer) valueAnimator.getAnimatedValue();
                ViewGroup.LayoutParams layoutParams = v.getLayoutParams();
                layoutParams.height = value;
                v.setLayoutParams(layoutParams);
            }
        });
        return animator;
    }

你也可以使用ObjectAnimator

ObjectAnimator.ofInt(your view, "left", 100, 250)
    .setDuration(250)
    .start();