안드로이드 자식뷰 강제 높이 구하기

private int getChildHeight(ViewGroup parentView) {
    final int measureSpecW = View.MeasureSpec.makeMeasureSpec(parentView.getWidth(), View.MeasureSpec.EXACTLY);
    final int measureSpecH = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
    int totalHeight = 0;
    for (int i = 0; i < parentView.getChildCount(); i++) {
        View childView = parentView.getChildAt(i);
        ViewGroup.LayoutParams p = (ViewGroup.LayoutParams) childView.getLayoutParams();
        int lpHeight = p.height;

        int childHeightSpec;
        if (lpHeight > 0) {
            childHeightSpec = View.MeasureSpec.makeMeasureSpec(lpHeight, View.MeasureSpec.EXACTLY);
        } else {
            childHeightSpec = measureSpecH;
        }
        childView.measure(measureSpecW, childHeightSpec);
        totalHeight += childView.getMeasuredHeight();
    }
    return totalHeight;
}