在运行时获取RecyclerView子视图的高度

Question

我正在尝试制作一个可扩展的TextView，当用户按下按钮时它会扩展/折叠。TextView和ImageButton位于CardView中，该CardView已添加到RecyclerView中。

展开/折叠效果很好，但是现在我只想在TextView高度超过某个最大高度时才添加ImageButton。但是，当我在LayoutManager的addView方法中评估高度时，它返回0，这可能是因为TextView还没有任何文本。

CardView获取新内容后，是否有我可以重写的回调方法可以用来评估TextView的高度？

编辑：我已经尝试过yigit建议onLayoutChildren

@Override
public void onLayoutChildren (RecyclerView.Recycler recycler, RecyclerView.State state) {
    super.onLayoutChildren(recycler, state);
    Log.d("LayoutManager","State Count: " + state.getItemCount());

    for (int i = 1; i < state.getItemCount(); i++) {
        View v = recycler.getViewForPosition(i);
        TextView ct = (TextView) v.findViewById(R.id.comment_text);
        Log.d("LayoutManager", "Comment height: " + ct.getMeasuredHeight());
    }
}

结果输出：

D/LayoutManager? State Count: 4
D/LayoutManager? Comment height: 0
D/LayoutManager? Comment height: 0
D/LayoutManager? Comment height: 0

Answer 1

LinearLayout.LayoutParams-根据您的主布局，它可以是RelativeLayout.LayoutParams。mParentContainer-这是RecyclerView-传递给您的适配器Utils.dpToPx（8 + 15）; -此处添加的边距coz不计入度量totalHeight + = 1；-使适配器绑定下一个视图持有者；）

在View Holder中：

int totalHeight = 0;
        for(int i=0; i<getItemCount(); i++){

            View chView = viewHolder.itemView;
            chView.measure(
                   View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
                    View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
            totalHeight += chView.getMeasuredHeight();
            totalHeight += Utils.dpToPx(8+15);
        }

        totalHeight += 1;
        LinearLayout.LayoutParams listParams = (LinearLayout.LayoutParams) mParentContainer.getLayoutParams();
        listParams.height = totalHeight;
        mParentContainer.setLayoutParams(listParams);