ScrollView中嵌套ListView问题

 1 public class MyListView extends ListView {
 2 
 3         public MyListView(Context context) {
 4             super(context);
 5         }
 6 
 7         public MyListView(Context context, AttributeSet attrs) {
 8             super(context, attrs);
 9         }
10 
11         public MyListView(Context context, AttributeSet attrs,int defStyle) {
12             super(context, attrs, defStyle);
13         }
14 
15         @Override
16         protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
17             int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
18                     MeasureSpec.AT_MOST);
19             super.onMeasure(widthMeasureSpec, expandSpec);
20         }
21        }

sv.scrollTo(0, 0);
sv.smoothScrollTo(0,0);