RecyclerView的Item縮放效果

要實現RecyclerView的Item縮放效果，可以通過自定義ItemAnimator來實現。以下是一個簡單的示例代碼，實現RecyclerView的Item縮放效果：

public class ScaleInItemAnimator extends DefaultItemAnimator {

    @Override
    public boolean animateAdd(RecyclerView.ViewHolder holder) {
        View view = holder.itemView;
        view.setScaleX(0.5f);
        view.setScaleY(0.5f);
        return super.animateAdd(holder);
    }

    @Override
    public boolean animateRemove(RecyclerView.ViewHolder holder) {
        final View view = holder.itemView;
        ObjectAnimator scaleX = ObjectAnimator.ofFloat(view, "scaleX", 1, 0.5f);
        ObjectAnimator scaleY = ObjectAnimator.ofFloat(view, "scaleY", 1, 0.5f);
        AnimatorSet animatorSet = new AnimatorSet();
        animatorSet.playTogether(scaleX, scaleY);
        animatorSet.setDuration(getAddDuration());
        animatorSet.addListener(new AnimatorListenerAdapter() {
            @Override
            public void onAnimationEnd(Animator animation) {
                dispatchRemoveFinished(holder);
                view.setScaleX(1);
                view.setScaleY(1);
            }
        });
        animatorSet.start();
        return true;
    }
}

然后在RecyclerView初始化時設置自定義的ItemAnimator：

RecyclerView recyclerView = findViewById(R.id.recyclerView);
recyclerView.setItemAnimator(new ScaleInItemAnimator());

這樣就可以實現RecyclerView的Item在添加和移除時的縮放效果了。你也可以根據需要對ItemAnimator進行進一步的定制和擴展。