怎么在android中使用View实现一个滑动删除效果

public class SlideDelete extends ViewGroup { private View leftView; private View rightView; private ViewDragHelper helper; //第一步关联构造方法 //第二步重写onMeasure和onLViewayout测量子View和布局子View public SlideDelete(Context context) {  this(context,null); } public SlideDelete(Context context, AttributeSet attrs) {  this(context, attrs,0); } public SlideDelete(Context context, AttributeSet attrs, int defStyleAttr) {  super(context, attrs, defStyleAttr);  helper = ViewDragHelper.create(this, callback); }}