BaseAdapter導致notifyDataSetChanged()無效的四個原因及處理方法

前一段時間在做一個項目的時候遇到了一個關於BaseAdapter的notifyDataSetChanged()方法無效問題，當時在網上搜了一個解決方案，今天又遇到了一個類似的問題，我在這裡做個記錄，防止以後再次發生，或者其他朋友再次遇到。

一、ScrollView中嵌套ListView或GridView

原因：兩個的滾動監聽衝突

解決方案：重寫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}/** * 為了取消滾動效果，可以放入滾動組建中重寫了此方法 */@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的外部容器重寫onTouchEvent(MotionEvent event)方法

詳細請看：http://blog.csdn.net/xxxzhi/article/details/12314775

這類問題解決方案很簡單，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("父類點擊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("父類滑動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("父類放開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、資料傳值問題

注意改變Adapter內的資料，如下：list_contents和toparr是改變後的資料

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

有一種錯誤的寫法就是直接調用notifyData方法

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

四、ViewGroup中notifyDataSetChanged()無效

@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());// }}

注釋掉onLayout中的if(changed)即可。