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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