Android ViewPager更新数据

protected PagerAdapter galleryAdapter = new PagerAdapter() {
        
        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
             return arg0 == ((View)arg1); 
        }
        
        @Override
        public int getCount() {
            return size;
        }
        
        @Override
        public Object instantiateItem(View container, int position) {
            return bindGalleryAdapterItemView(container, position);
        }
        
        @Override
        public void destroyItem(View container, int position, Object object) {
             ((ViewPager) container).removeView((View) object); 
        };
        
        @Override  
        public void finishUpdate(View arg0) {}  
          
        @Override
        public void restoreState(android.os.Parcelable state, ClassLoader loader) {
            
        };
  
        @Override  
        public Parcelable saveState() {  
            return null;  
        }  
  
        @Override  
        public void startUpdate(View arg0) {}  
        
        @Override
        public int getItemPosition(Object object) {
　　　　　　　//POSITION_NONE 是一个PagerAdapter的内部常量，值是-2，
            return POSITION_NONE;
        }

    };