ListView调整高度

listView 有时候项目太少占用空间太大，如何能够自动控制

自适用大小

package com.customcontrols; 
public class NoScrollListView extends ListView 
{ 
    @Override 
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) 
    { 
        super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(MeasureSpec.UNSPECIFIED, 0) ); 
 
        // here I assume that height's being calculated for one-child only, seen it in ListView's source which is actually a bad idea 
        int childHeight = getMeasuredHeight() - (getListPaddingTop() + getListPaddingBottom() +  getVerticalFadingEdgeLength() * 2); 
 
        int fullHeight = getListPaddingTop() + getListPaddingBottom() + childHeight*(getCount()); 
 
        setMeasuredDimension(getMeasuredWidth(), fullHeight); 
    } 
}