ScroolView中的ListView冲突问题解决方案

思路：

Listview和ScrollView都具有滚动能力，对于这样的控件在嵌套在一起使用后就会出现问题。

问题一：ScrollView与ListView嵌套导致ListView显示不完全

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FooterView两部分，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一方案效果，具体来说缺点是大材小用，但也是合理的解决方法

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));
}
}