Android:如何在 RecyclerView 中展开和折叠 cardView 大小

Question

我需要在运行时展开和折叠 RecyclerView 中的 CardView 大小。我使用 RecyclerView 显示列表，使用 CardView 作为 RecyclerView 项。由于我是这个概念的新手，请帮助我。

Answer 1

我已经扩展了运行时间。像这样，

在 onCreateView() 上设置我的 View

descriptionCardView.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver
    .OnPreDrawListener() {
@Override
public boolean onPreDraw() {
    detailProductDescription.getViewTreeObserver().removeOnPreDrawListener(this);
    // save the full height
    descriptionViewFullHeight = detailProductDescription.getHeight();

    // initially changing the height to min height
    ViewGroup.LayoutParams layoutParams = descriptionCardView.getLayoutParams();
    layoutParams.height = (int) getActivity().getResources().getDimension(R.dimen
            .product_description_min_height);
    descriptionCardView.setLayoutParams(layoutParams);

    return true;
 }
});

和onClickingcardview

@OnClick(R.id.detail_product_description)
void onProductDescriptionClicked(View view) {
    toggleProductDescriptionHeight();
}

我正在设置 CardView 的高度以展开和折叠。

private int descriptionViewFullHeight;    
private void toggleProductDescriptionHeight() {

    int descriptionViewMinHeight = (int) getActivity().getResources().getDimension(R.dimen
            .product_description_min_height);
    if (descriptionCardView.getHeight() == descriptionViewMinHeight) {
        // expand
        ValueAnimator anim = ValueAnimator.ofInt(descriptionCardView.getMeasuredHeightAndState(),
                descriptionViewFullHeight);
        anim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                int val = (Integer) valueAnimator.getAnimatedValue();
                ViewGroup.LayoutParams layoutParams = descriptionCardView.getLayoutParams();
                layoutParams.height = val;
                descriptionCardView.setLayoutParams(layoutParams);
            }
        });
        anim.start();
    } else {
        // collapse
        ValueAnimator anim = ValueAnimator.ofInt(descriptionCardView.getMeasuredHeightAndState(),
                descriptionViewMinHeight);
        anim.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
            public void onAnimationUpdate(ValueAnimator valueAnimator) {
                int val = (Integer) valueAnimator.getAnimatedValue();
                ViewGroup.LayoutParams layoutParams = descriptionCardView.getLayoutParams();
                layoutParams.height = val;
                descriptionCardView.setLayoutParams(layoutParams);
            }
        });
        anim.start();
    }
}