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Android ListView与ScrollView冲突的解决方法总结

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这篇文章主要介绍了Android ListView与ScrollView冲突的解决方法总结的相关资料,需要的朋友可以参考下

Android ListView与ScrollView冲突的解决方法总结

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)); 
 } 
} 

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