BaseAdapter导致notifyDataSetChanged()无效的四个原因及处理方法

前一段时间在做一个项目的时候遇到了一个关于BaseAdapter的notifyDataSetChanged()方法无效问题，当时在网上搜了一个解决方法，今天又遇到了一个类似的问题，我在这里做个记录，防止以后再次发生，或者其他朋友再次遇到。

一、ScrollView中嵌套ListView或GridView

原因：两个的滚动监听冲突

解决方法：重写ListView或GridView

package com.meritit.lottery.view;import android.content.Context;import android.util.AttributeSet;import android.widget.ListView;public class SerialListView extends ListView {public SerialListView(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);// TODO Auto-generated constructor stub}public SerialListView(Context context, AttributeSet attrs) {super(context, attrs);// TODO Auto-generated constructor stub}public SerialListView(Context context) {super(context);// TODO Auto-generated constructor stub}/** * 为了取消滚动效果，可以放入滚动组建中重写了此方法 */@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,MeasureSpec.AT_MOST);super.onMeasure(widthMeasureSpec, expandSpec);}}

二、ListView或GridView的外部容器重写onTouchEvent(MotionEvent event)方法

详细请看：http://blog.csdn.net/xxxzhi/article/details/12314775

这类问题解决方法很简单，只需要onTouchEvent返回false即可

例如：

@Overridepublic boolean onTouchEvent(MotionEvent event) {// TODO Auto-generated method stub                               final int action = event.getAction();            final float x = event.getX();            final float y = event.getY();                        switch (action) {            case MotionEvent.ACTION_DOWN:         System.out.println("父类点击onTouchEvent");          Log.i("", "onTouchEvent  ACTION_DOWN");                  if (mVelocityTracker == null) {                mVelocityTracker = VelocityTracker.obtain();                mVelocityTracker.addMovement(event);     }                     if (!mScroller.isFinished()){                    mScroller.abortAnimation();                }                            mLastMotionX = x;                       mLastMotionY = y;                       break;                            case MotionEvent.ACTION_MOVE:          System.out.println("父类滑动onTouchEvent");           int deltaX = (int)(mLastMotionX - x);                      if (IsCanMove(deltaX))           {         if (mVelocityTracker != null)           {              mVelocityTracker.addMovement(event);            }                 mLastMotionX = x;                   scrollBy(deltaX, 0);           }                    break;                            case MotionEvent.ACTION_UP:               System.out.println("父类放开onTouchEvent");        int velocityX = 0;            if (mVelocityTracker != null)            {            mVelocityTracker.addMovement(event);             mVelocityTracker.computeCurrentVelocity(1000);              velocityX = (int) mVelocityTracker.getXVelocity();            }                                           if (velocityX > SNAP_VELOCITY && mCurScreen > 0) {                       // Fling enough to move left                       Log.e(TAG, "snap left");                    snapToScreen(mCurScreen - 1);                   } else if (velocityX < -SNAP_VELOCITY                           && mCurScreen < getChildCount() - 1) {                       // Fling enough to move right                       Log.e(TAG, "snap right");                    snapToScreen(mCurScreen + 1);                   } else {                       snapToDestination();                   }                                          if (mVelocityTracker != null) {                       mVelocityTracker.recycle();                       mVelocityTracker = null;                   }             //      mTouchState = TOUCH_STATE_REST;            break;              }                        return false;    }

三、数据传值问题

注意改变Adapter内的数据，如下：list_contents和toparr是改变后的数据

mycqbaseAdapter.contents=list_contents;mycqtitleAdapter.toparr = toparr;mycqbaseAdapter.notifyDataSetChanged();mycqtitleAdapter.notifyDataSetChanged();

有一种错误的写法就是直接调用notifyData方法

mycqbaseAdapter.notifyDataSetChanged();mycqtitleAdapter.notifyDataSetChanged();

四、ViewGroup中notifyDataSetChanged()无效

@Override   protected void onLayout(boolean changed, int l, int t, int r, int b) {// if (changed) {menu_view = getChildAt(0);content_view = getChildAt(1);content_view.measure(0, 0);content_view.layout(0, 0, getWidth(), getHeight());// }}

注释掉onLayout中的if(changed)即可。