viewpager无限轮播

package animtest.com.example.e531.viewpager_demo;

import android.os.Handler;

import android.os.Message;

import android.support.v4.view.ViewPager;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.widget.ImageView;

import android.widget.LinearLayout;

import java.util.ArrayList;

import java.util.List;

public class MainActivity extends AppCompatActivity {

    private Handler myHandler=new Handler(){

        @Override

        public void handleMessage(Message msg) {

            //获取当前正在显示的页面

            int index=viewPager.getCurrentItem();

            viewPager.setCurrentItem(index+1);

            //改变小圆点

            setSelectedPoint(index+1);

            //延迟发送消息

            sendEmptyMessageDelayed(1,2000);

        }

    };

    private ViewPager viewPager;

    private LinearLayout linPoint;

    private ImageView[] imgArray;

    private List<String> list;

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        viewPager = (ViewPager) findViewById(R.id.vp);

        linPoint = (LinearLayout) findViewById(R.id.linpoint);

        //数据.....装的是path路径

        list = new ArrayList<>();

        list.add("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1505151721118&di=649c9a43aed72fbc4d99ec1a031510c6&imgtype=0&src=http%3A%2F%2Fimg.zcool.cn%2Fcommunity%2F015c7d574b9f8f6ac72525aee98351.jpg");

        list.add("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1505151956771&di=0eb6f306991d24b67a13ceb336f80102&imgtype=0&src=http%3A%2F%2Fi0.hdslb.com%2Fbfs%2Farchive%2F00613def3f1beb7a35ae136341be2b589bc46a2d.jpg_320x200.jpg");

        list.add("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1505151847685&di=c7a4b5d08ec43fa629bcb690039a7629&imgtype=0&src=http%3A%2F%2Fattimg.dospy.com%2Fimg%2Fday_080625%2F20080625_2e91a10c444877e88827vri2ZKdGMvQo.jpg");

        list.add("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1505151825129&di=70bf74b87d8a15cb91a2d79f15ed0eaf&imgtype=0&src=http%3A%2F%2Fattimg.dospy.com%2Fimg%2Fday_081016%2F20081016_fee215664d5740e56c13E2YB8giERFEX.jpg");

        list.add("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1505746504&di=930c4d677a02328a142d6fa85ed14580&imgtype=jpg&er=1&src=http%3A%2F%2Fattimg.dospy.com%2Fimg%2Fday_090113%2F20090113_6ac58b42bea94f0b318e1B6BZb5lPZl5.jpg");

        imgArray=new ImageView[list.size()];

        viewPager.setAdapter(new MyPagerAdapter(this,list));

        //使页面 可以向左滑动

        viewPager.setCurrentItem(list.size()*100);

        //实现自动播放

        myHandler.sendEmptyMessageDelayed(1,2000);

        initPoint();

    }

    //0,1,2,3,4,......Integer.maxvalue

    public  void setSelectedPoint(int pageIndex){

        //循环imageview控件

        //计算要选中小圆点的下标

        int selectedIndex=pageIndex%list.size();

        for(int i=0;i<list.size();i++){

            if(i==selectedIndex){

                imgArray[i].setImageResource(R.drawable.my_point_selected);//小红点

            }else{

                imgArray[i].setImageResource(R.drawable.my_point_unselected);//小灰点

            }

        }

    }

    /**

     * 初使化小圆点

     */

    private void initPoint() {

        for(int i=0;i<list.size();i++){

            //第一步

            ImageView img=new ImageView(this);

            //图片的缩放方式

            img.setScaleType(ImageView.ScaleType.FIT_XY);

            if(i==0){

                //使用shape画小圆点

                img.setImageResource(R.drawable.my_point_selected);//第二步

            }else{

                img.setImageResource(R.drawable.my_point_unselected);

            }

            //img对象 设置控件的宽度与高度

            LinearLayout.LayoutParams params=new LinearLayout.LayoutParams(30,30);

            //设置右间隔 10px

            params.setMargins(0,0,10,0);

            //添加到容器中

            linPoint.addView(img,params);//第三步

            //添加到数组中

            imgArray[i]=img;

        }

    }

}

//MyPagerAdapter

package animtest.com.example.e531.viewpager_demo;

import android.content.Context;

import android.support.v4.view.PagerAdapter;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ImageView;

import com.nostra13.universalimageloader.core.ImageLoader;

import java.util.List;

import animtest.com.example.e531.viewpager_demo.utils.ImageUtils;

/**

 * Created by e531 on 2017/11/13.

 */

public class MyPagerAdapter  extends PagerAdapter{

    private Context context;

//    private int[] imgArray=new int[]{R.mipmap.a0,R.mipmap.a1,R.mipmap.a2};

    //用于存放网络图片的url地址

    private List<String> imgUrl;

    public MyPagerAdapter(Context context,List<String> imgUrl) {

        this.context = context;

        this.imgUrl=imgUrl;

    }

    //返回页面的数量

    @Override

    public int getCount() {

        return Integer.MAX_VALUE;

    }

    @Override

    public boolean isViewFromObject(View view, Object object) {

        return view==object;

    }

    //0~getCount返回的值-1

    @Override

    public Object instantiateItem(ViewGroup container, int position) {

        //返回当前显示的视图

        ImageView imageView = new ImageView(context);

        //图片的绽放方式

        imageView.setScaleType(ImageView.ScaleType.FIT_XY);

        //0,1,2

//        imageView.setImageResource(imgArray[position%imgArray.length]);

        //使用ImageLoader下载图片

        ImageLoader.getInstance().displayImage(imgUrl.get(position%imgUrl.size()),

                imageView, ImageUtils.getImageOptions());

        //添加到容器

        container.addView(imageView);

        return imageView;

    }

    @Override

    public void destroyItem(ViewGroup container, int position, Object object) {

        container.removeView((View) object);

    }

}