当ViewGroup测量，以及为gone的时候怎么获取ViewGroup的高度

1.测量时，需要自定义ViewGroup，实现onMeasure方法

   @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int measuredWidth = 0;
        int measuredHeight = 0;
        final int childCount = getChildCount();
        measureChildren(widthMeasureSpec, heightMeasureSpec);

        int widthSpaceSize = MeasureSpec.getSize(widthMeasureSpec);
        int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
        int heightSpaceSize = MeasureSpec.getSize(heightMeasureSpec);
        int heightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
        if (childCount == 0) {
            setMeasuredDimension(0, 0);
        } else if (widthSpecMode == MeasureSpec.AT_MOST && heightSpecMode == MeasureSpec.AT_MOST) {
            final View childView = getChildAt(0);
            measuredWidth = childView.getMeasuredWidth() * childCount;
            measuredHeight = childView.getMeasuredHeight();
            setMeasuredDimension(measuredWidth, measuredHeight);
        } else if (heightSpecMode == MeasureSpec.AT_MOST) {
            final View childView = getChildAt(0);
            measuredHeight = childView.getMeasuredHeight();
            setMeasuredDimension(widthSpaceSize, childView.getMeasuredHeight());
        } else if (widthSpecMode == MeasureSpec.AT_MOST) {
            final View childView = getChildAt(0);
            measuredWidth = childView.getMeasuredWidth() * childCount;
            setMeasuredDimension(measuredWidth, heightSpaceSize);
        }
    }

 然后在调用this.getMeasuredHeight();就可以获取了。

 this.getMeasuredHeight();

 2.当view为gone的时候怎么获取view的高度

在项目开发中，遇到了 当view为gone时 测量高度一直为0，解决办法：

mView.getViewTreeObserver().addOnGlobalLayoutListener( 
    new OnGlobalLayoutListener(){
 
        @Override
        public void onGlobalLayout() {
            // gets called after layout has been done but before display
            // so we can get the height then hide the view    
 
            mHeight = mView.getHeight();  
 
            mView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
            mView.setVisibility(View.GONE);
        }
 
});

 默认先让他显示，而加载完成，则进行View.GONE，就可以了。