工作中遇到ListView和ScrollView的冲突

众所周知ListView与ScrollView都具有滚动能力，对于这样的View控件，当ScrollView与ListView相互嵌套会成为一种问题：

 问题一:ScrollView与ListView嵌套导致ListView显示不全面

 问题二:ScrollView不能正常滑动

解决方式一:

ScrollView+LinearLayout+ListView可以换成ScrollView+LinearLayout+LinearLayout，对于开发中，ScrollView所能滚动的样式形式各异，另外的话，ScrollView所显示的内容肯定不会太多，因此这种方案是合理而且可选的

解决方式二：

同样是替换：ListView具有HeaderView与FooterView2部分，因此，在非下拉刷新，上拉加载的需求中，完全可以使用ListView来代替ScrollView，因此是合理可选的方案

解决方式三：

主动计算和设置ListView的高度，这样的结果最终得出类似解决方案一效果，具体来说缺点是大材小用，但也是合理的解决办法。

    public  class  Utility {
        public  static  void  setListViewHeightBasedOnChildren(ListView listView) {
            ListAdapter listAdapter = listView.getAdapter();
            if  (listAdapter ==  null ) {
                return ;
            }

            int  totalHeight =  0 ;
            for  ( int  i =  0 ; i < listAdapter.getCount(); i++) {
                View listItem = listAdapter.getView(i,  null , listView);
                listItem.measure( 0 ,  0 );
                totalHeight += listItem.getMeasuredHeight();
            }

            ViewGroup.LayoutParams params = listView.getLayoutParams();
            params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() -  1 ));
            listView.setLayoutParams(params);
        }
    }

解决方式四：

复写ScrollView，从事件方向进行处理，缺点是灵活性不够好

public  class  ListScrollView  extends  ScrollView {
 private  List list =  new  ArrayList();
 private  int  scrollPaddingTop;  // scrollview的顶部内边距
 private  int  scrollPaddingLeft; // scrollview的左侧内边距
 private  int [] scrollLoaction =  new  int [ 2 ];  // scrollview在窗口中的位置
 private  final  static  int  UPGLIDE =  0 ;
 private  final  static  int  DOWNGLIDE =  1 ;
 private  int  glideState;
 public  ListScrollView(Context context, AttributeSet attrs) {
  super (context, attrs);
 }
 private  int  downY =  0 ;
 private  int  moveY =  0 ;

 @Override
 public  boolean  dispatchTouchEvent(MotionEvent ev) {
  switch  (ev.getAction()) {
  case  MotionEvent.ACTION_DOWN:
   downY = ( int ) ev.getY();
   //System.out.println("actiondown" + ev.getY());
   break ;
  case  MotionEvent.ACTION_MOVE:
   moveY= ( int ) ev.getY();
   //System.out.println("move" + moveY + "down" + downY);
   if ((moveY - downY) >=  0 ) {
    //System.out.println("'''''''''DOWNGLIDE'''''''''''");
    glideState = DOWNGLIDE;
   }  else  {
    //System.out.println("'''''''''UPGLIDE'''''''''''");
    glideState = UPGLIDE;
   }
   break ;
  case  MotionEvent.ACTION_UP:
  default :
   break ;
  }
  return  super .dispatchTouchEvent(ev);
 }
 @Override
 public  boolean  onInterceptTouchEvent(MotionEvent ev) {
  // 该事件的xy是以scrollview的左上角为00点而不是以窗口为00点
  int  x = ( int ) ev.getX() + scrollLoaction[ 0 ];
  int  y = ( int ) ev.getY() + scrollLoaction[ 1 ];
  for  ( int  i =  0 ; i < list.size(); i++) {
   ListView listView = list.get(i);
   int [] location =  new  int [ 2 ];
   listView.getLocationInWindow(location);
   int  width = listView.getWidth();
   int  height = listView.getHeight();
   // 在listview的位置之内则可以滑动
   if  (x >= location[ 0 ] + scrollPaddingLeft
     && x <= location[ 0 ] + scrollPaddingLeft + width
     && y >= location[ 1 ] + scrollPaddingTop
     && y <= location[ 1 ] + scrollPaddingTop + height) {
    //System.out.println(glideState);
    if (( (listView.getLastVisiblePosition() == (listView.getCount()- 1 )) && (glideState == UPGLIDE) ) ) {
     //System.out.println("up");
     break ;
    }
    if (( (listView.getFirstVisiblePosition() ==  0 ) && (glideState == DOWNGLIDE))) {
     //System.out.println("down");
     break ;
    }
    return  false ;  //让子控件直接处理
   }
  }
  return  super .onInterceptTouchEvent(ev);
 }
 @Override
 public  boolean  onTouchEvent(MotionEvent ev) {
  return  super .onTouchEvent(ev);
 }


 private  void  findAllListView(View view) {
  if  (view  instanceof  ViewGroup) {
   int  count = ((ViewGroup) view).getChildCount();
   for  ( int  i =  0 ; i < count; i++) {
    if  (!(view  instanceof  ListView)) {
     findAllListView(((ViewGroup) view).getChildAt(i));
    }
   }
   if  (view  instanceof  ListView) {
    list.add((ListView) view);
   }
  }
 }
 @Override
 protected  void  onDraw(Canvas canvas) {
  super .onDraw(canvas);
  scrollPaddingTop = getTop();
  scrollPaddingLeft = getLeft();
  getLocationInWindow(scrollLoaction);
 }
 @Override
 protected  void  onLayout( boolean  changed,  int  l,  int  t,  int  r,  int  b) {
  super .onLayout(changed, l, t, r, b);
  if  ( this .getChildCount() !=  1 ) {
   try  {
    throw  new  ScrollException();
   }  catch  (ScrollException e) {
    e.printStackTrace();
   }
  }
  list.clear();
  findAllListView( this .getChildAt( 0 ));
 }
}