如何实现viewpager自动轮播

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//主界面

package com.example.viewpager;


import java.util.ArrayList;
import java.util.List;


import com.example.adapter.MyPagerAdapter;


import android.R.integer;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.LayoutParams;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
/**
 * 使用viewpager实现滑动,当滑动页面时,页面下的小圆点跟随页面的滑动而改变
 * @author 浅议爱
 *
 */


public class MainActivity extends Activity {

private ViewPager mViewPager;
    private LinearLayout lin;
    private List<View> views;
    
    //定义适配器
    private MyPagerAdapter adapter;


    
    //上一个知识点
    private int lastPointIndex=0;
    //使用handler完成操作
    Handler handler=new Handler(){
    public void handleMessage(android.os.Message msg) {
    //获取viewpager滑动的当前位置
    int currentItem=mViewPager.getCurrentItem();
    mViewPager.setCurrentItem(currentItem+=1);
    //持续两秒,
    handler.sendEmptyMessageAtTime(1, 2000);
    };
    };
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //获取控件id
        mViewPager=(ViewPager) findViewById(R.id.myviewpager);
        lin=(LinearLayout) findViewById(R.id.aaaa);
        //获取控件id
        //定义方法,加载数据
        intodata();
        
        adapter=new MyPagerAdapter(getApplicationContext(),views);
        mViewPager.setAdapter(adapter);
        
        int item=Integer.MAX_VALUE/2-Integer.MAX_VALUE/2%views.size();
        mViewPager.setCurrentItem(item);
        handler.sendEmptyMessageAtTime(1, 2000);
        
        //设置viewapgee滑动监听
        mViewPager.setOnPageChangeListener(new OnPageChangeListener() {
//viewpager当前展示的页面
@Override
public void onPageSelected(int arg0) {
// TODO Auto-generated method stub
int myindex=arg0%views.size();
//改变指示点的状态,将当前图片的enable设为true
lin.getChildAt(myindex).setEnabled(true);
//将上一个指示点的enable设为false
lin.getChildAt(lastPointIndex).setEnabled(false);

//更新lastPointIndex的值
lastPointIndex=myindex;

}

//当viwpager页面滑动时,
@Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
// TODO Auto-generated method stub
}
//当停止滑动时
@Override
public void onPageScrollStateChanged(int arg0) {
// TODO Auto-generated method stub
}
});
    }


    /**
     * 加载viewpager页面数据
     */
private void intodata() {
// TODO Auto-generated method stub
views=new ArrayList<View>();
views.add(View.inflate(getApplicationContext(), R.layout.viewpager01, null));
views.add(View.inflate(getApplicationContext(), R.layout.viewpager02, null));
views.add(View.inflate(getApplicationContext(), R.layout.viewpager03, null));
views.add(View.inflate(getApplicationContext(), R.layout.viewpager04, null));


for (int i = 0; i < views.size(); i++) {
ImageView point=new ImageView(this);
LinearLayout.LayoutParams params=new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, -2);
params.leftMargin=15;
point.setLayoutParams(params);
//设置小黑点的背景
point.setBackgroundResource(R.drawable.point_bg);
//添加到布局文件上
lin.addView(point);

if (i==0) {
point.setEnabled(true);
}else{
point.setEnabled(false);
}
}
}


}


//适配器

package com.example.adapter;


import java.util.List;


import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.view.View;
import android.view.ViewGroup;


public class MyPagerAdapter extends PagerAdapter {
Context applicationContext;
List<View> views;


public MyPagerAdapter(Context applicationContext, List<View> views) {
super();
this.applicationContext = applicationContext;
this.views = views;
}


@Override
public int getCount() {
// TODO Auto-generated method stub
//设为最大值
return Integer.MAX_VALUE;
}


@Override
public Object instantiateItem(ViewGroup container, int position) {
// TODO Auto-generated method stub
View view=views.get(position%views.size());
container.addView(view);
return view;


}

@Override
public void destroyItem(ViewGroup container, int position, Object object) {
// TODO Auto-generated method stub
container.removeView((View) object);

// super.destroyItem(container, position, object);
}

@Override
public boolean isViewFromObject(View arg0, Object arg1) {
// TODO Auto-generated method stub
return arg0==arg1;
}


}

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