获取listview当前滚动的高度

public int getScrollY() {

     View c = mListView.getChildAt(0);

     if (c == null ) {

         return 0;

     }

     int firstVisiblePosition = mListView.getFirstVisiblePosition();

     int top = c.getTop();

     return -top + firstVisiblePosition * c.getHeight() ;

}