//网络请求数据工具类

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

public class HttpUrlUtils {

private static String string;

public static String requestData(String s){
    HttpURLConnection urlConnection;

    try {
        URL url = new URL(s);
        urlConnection = (HttpURLConnection) url.openConnection();
        urlConnection.setReadTimeout(5000);
        urlConnection.setConnectTimeout(5000);
        urlConnection.setRequestMethod("GET");
        int responseCode = urlConnection.getResponseCode();
        if (responseCode==200){
            string = readstring(urlConnection.getInputStream());
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
   return string;
}
  //将流转换为数据
private static String readstring(InputStream inputStream) throws IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader(inputStream));
    StringBuilder stringBuilder = new StringBuilder();
    String temp="";
    while ((temp=br.readLine())!=null){
        stringBuilder.append(temp);
    }
    return stringBuilder.toString();
}

}

MainActivity

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import android.widget.LinearLayout;
import android.widget.TextView;

import com.example.qmy.a1020.R;

import com.example.qmy.a1020.adapter.ImageAdapter;
import com.example.qmy.a1020.model.Banner;
import com.example.qmy.a1020.utils.HttpUrlUtils;
import com.google.gson.Gson;

import java.util.List;

public class AFragment extends android.support.v4.app.Fragment {
ViewPager vpager；
ImageAdapter imageAdapter;
LinearLayout line;
TextView tv;
View view;
Banner banner;

Handler handler = new Handler(){

    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        
        switch (msg.what){
            case 0:
                imageAdapter.setDate((List<Banner.DataBean>) msg.obj);
                //解决开始无法向右滑动的问题
                vpager.setCurrentItem(5000);
                break;
                
            case 1:
                //无限轮播
                
                int currentItem = vpager.getCurrentItem();
                currentItem++;
                vpager.setCurrentItem(currentItem);
                handler.sendEmptyMessageDelayed(1,1000);

        }


    }
};
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    view = View.inflate(getActivity(), R.layout.afrag, null);

    vpager = view.findViewById(R.id.vpager);
    line = view.findViewById(R.id.line);
    tv = view.findViewById(R.id.tv);

    //请求数据
    new Thread(new Runnable() {
        @Override
        public void run() {
            String string = HttpUrlUtils.requestData("http://www.xieast.com/api/banner.php");
            //解析
            banner = new Gson().fromJson(string, Banner.class);
            handler.sendMessage(handler.obtainMessage(0,banner.getData()));
        }
    }).start();

    //适配器
    imageAdapter = new ImageAdapter(getActivity());
    vpager.setAdapter(imageAdapter);

    handler.sendEmptyMessageDelayed(1,1000);

    //设置小圆点
    settinground();

    //viewapger的滑动监听事件
    vpager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int i, float v, int i1) {
             //设置文本
            int currentItem = vpager.getCurrentItem();
           chageText(currentItem % banner.getData().size());
        }

        @Override
        public void onPageSelected(int i) {

        }

        @Override
        public void onPageScrollStateChanged(int i) {

        }
    });
    //触摸事件
    vpager.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            switch (event.getAction()){
                case MotionEvent.ACTION_DOWN:
                    handler.removeMessages(1);
                    break;
                case MotionEvent.ACTION_MOVE:
                    handler.removeMessages(1);

                    break;
                case MotionEvent.ACTION_UP:
                    handler.sendEmptyMessageDelayed(1,1000);
                    break;
            }
            return false;
        }
    });
    return view;
}

//设置文本
private void chageText(int position) {
    String title = banner.getData().get(position).getTitle();
    tv.setText(title);
    //小圆点
    for (int x =0;x<banner.getData().size();x++){
        //获取子控件
        View child = line.getChildAt(x);
        child.setBackgroundResource(x==position?R.mipmap.dot_focus:R.mipmap.dot_normal);

    }
}

//设置圆点
private void settinground() {
    View view = new View(getActivity());
    //设置背景图片
    view.setBackgroundResource(R.mipmap.dot_normal);
    //设置宽高
    LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(20, 20);

    layoutParams.leftMargin=10;
    //设置给view
    view.setLayoutParams(layoutParams);
    line.addView(view);

}

}
//适配器
package com.example.qmy.a1020.adapter;

import android.support.annotation.NonNull;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.PagerAdapter;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

import com.example.qmy.a1020.model.Banner;
import com.example.qmy.a1020.utils.ImageLoaderConfing;
import com.nostra13.universalimageloader.core.ImageLoader;

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

public class ImageAdapter extends PagerAdapter {

private final FragmentActivity activity;
private final List<Banner.DataBean> imagelist;

public ImageAdapter(FragmentActivity activity) {
    this.activity = activity;
    imagelist = new ArrayList<>();
}

public void setDate(List<Banner.DataBean> obj) {
    this.imagelist.clear();
    this.imagelist.addAll(obj);
    notifyDataSetChanged();
}
@Override
public int getCount() {
    if (imagelist.size()==0){
        return 0;
    }else {
       return Integer.MAX_VALUE;
    }
}

@Override
public boolean isViewFromObject(@NonNull View view, @NonNull Object o) {
    return view==o;
}

@NonNull
@Override
public Object instantiateItem(@NonNull ViewGroup container, int position) {
    ImageView imageView = new ImageView(activity);
    ImageLoader.getInstance().displayImage(imagelist.get(position % imagelist.size()).getImg(),
            imageView,ImageLoaderConfing.getimageoption(activity));
    container.addView(imageView);
    return imageView;
}

@Override
public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
    container.removeView((View) object);
}

}