今天碰到很诡异的问题，viewpager中放置至少三张图片的时候能够正常实现循环滑动，只放置一张或者两张的时候就不行。

后来发现问题症结：viewpager需要保证既可以向左滑动，又可以向右滑动，因此当前显示viｅｗ的左侧和右侧都是存在的，只有超过这三个范围之外的才对其调用ｄｅｓｔｏｒｙ方法。

循环实现的代码如下：

package com.wot.cloudsensing.carrotfarm.adapter;import java.util.ArrayList;import com.wot.cloudsensing.carrotfarm.R;import android.content.Context;import android.support.v4.view.PagerAdapter;import android.support.v4.view.ViewPager;import android.view.View;import android.view.ViewGroup;import android.widget.ImageView;import android.widget.LinearLayout.LayoutParams;public class ViewPagerAdapter extends PagerAdapter {    private ArrayList
     
       imageviews;    private int size = 0;    public ViewPagerAdapter(ArrayList
      
        views) {        this.imageviews = views;        this.size = views.size();    }    @Override    public int getCount() {        return Integer.MAX_VALUE;    }    @Override    public boolean isViewFromObject(View arg0, Object arg1) {        return arg0 == arg1;    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {        System.out.println("111  destroyItem position = "                + (position % imageviews.size()));        ((ViewPager) container).removeView(imageviews.get(position                % imageviews.size()));    }    @Override    public Object instantiateItem(ViewGroup container, int position) {        System.out.println("111  instantiateItem instantiateItem  position = "                + (position % imageviews.size()));        ((ViewPager) container).addView(                imageviews.get(position % imageviews.size()), 0);        return imageviews.get(position % imageviews.size());    }}