类似Google Inbox的RecyclerView项打开动画

Question

目前，我正在尝试实现类似于Google Inbox的RecyclerView行为，并且对邮件打开动画非常好奇。

我的问题是：他们是如何做到的？我的意思是，他们使用了哪种方法？他们使用了ItemAnimator.dispatchChangeStarting()并将其高度更改为填充父级吗？还是其他的方法？如果确实是这样，他们是如何通过拉手势将其关闭而使底层RecyclerView元素略微可见。

有人可以帮忙指向一些库或代码片段/示例吗？

- Alviere

Answer 1

你的意思是：在recyclerview中加载项目，或者加载下一页时加载一次项目。我会举一个例子来说明如何在recyclerview中加载项目并添加动画效果。

public class CreateAnimationView {

private static int contador;
Integer colorFrom = R.color.myAccentColor;
Integer colorTo = Color.RED;

public static AnimatorSet createAnimation(View view) {
    ObjectAnimator fadeOut = ObjectAnimator.ofFloat(view, "alpha",
            0f);
    fadeOut.setDuration(300);
    ObjectAnimator mover = ObjectAnimator.ofFloat(view,
            "translationX", -500f, 0f);
    mover.setDuration(400);
    ObjectAnimator fadeIn = ObjectAnimator.ofFloat(view, "alpha",
            0f, 1f);
    fadeIn.setDuration(300);
    AnimatorSet animatorSet = new AnimatorSet();

    animatorSet.play(mover);
    animatorSet.start();
    return animatorSet;

 }
... more animations methods.
}

在您的RecyclerViewAdapter中：

@Override
public void onBindViewHolder(ViewHolder viewHolder, int position) {

    GruposCardView gruposCardView = gruposCardViews.get(position);

    CreateAnimationView.createAnimationRandom(viewHolder.cardView);
   ...}

如果不是在RecyclerView中，您可以传递一个布局并使用此动画，或从此创建一个动画。

 public static AnimatorSet createAnimationCollapseXY(View view) {
    ObjectAnimator scaleXOut = ObjectAnimator.ofFloat(view, "scaleX", 1f, 0f).setDuration(400);
    ObjectAnimator scaleXIn = ObjectAnimator.ofFloat(view, "scaleX", 0f, 1f).setDuration(300);
    ObjectAnimator scaleYOut = ObjectAnimator.ofFloat(view, "scaleY", 1f, 0f).setDuration(400);
    ObjectAnimator scaleYIn = ObjectAnimator.ofFloat(view, "scaleY", 0f, 1f).setDuration(300);
    ObjectAnimator rotateClockWise = ObjectAnimator.ofFloat(view, "rotation", 0f, 360f).setDuration(400);
    ObjectAnimator rotateCounterClockWise = ObjectAnimator.ofFloat(view, "rotation", 0f, -360f).setDuration(400);


    AnimatorSet animatorSet = new AnimatorSet();

    animatorSet.playTogether(scaleXIn, scaleYIn);
    //animatorSet.setStartDelay(1200);
    animatorSet.start();
    return animatorSet;
}

- Emmanuelguther