/**
  * 对高度和宽度进行统计 然后设置gridView的宽高。
  * @param numColumns 设定行数
  * @param gridView 
  */
public static void calGridViewSumWH(int numColumns ,GridView gridView) {
  // 获取GridView对应的Adapter
  ListAdapter listAdapter = gridView.getAdapter();
  if (listAdapter == null) {
   return;
  }
  int totalHeight = 0;
  int totalWidth = 0;
  for (int i = 0, len = listAdapter.getCount(); i < len; i++) { // listAdapter.getCount()返回数据项的数目
   View listItem = listAdapter.getView(i, null, gridView);
   listItem.measure(0, 0); // 计算子项View 的宽高
   totalWidth = listItem.getMeasuredWidth();
   if ((i+1)%numColumns == 0) {
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
     totalHeight += listItem.getMeasuredHeight() + gridView.getVerticalSpacing(); // 统计所有子项的总高度
    } else {
     totalHeight += listItem.getMeasuredHeight();
    }
   }

   if ((i+1) == len && (i+1)%numColumns != 0) {
    totalHeight += listItem.getMeasuredHeight(); // 统计所有子项的总高度
   }
  }
  if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
   totalHeight += 20;
  }
  if (listAdapter.getCount() < numColumns) {
   gridView.setNumColumns(listAdapter.getCount());
  }
  ViewGroup.LayoutParams params = gridView.getLayoutParams();
  params.height = totalHeight;
  params.width = totalWidth * listAdapter.getCount();
  gridView.setLayoutParams(params);
 }