自动轮播

<?xml version="1.0" encoding="utf-8"?><RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="200dp"    tools:context="bbb.bwie.com.gson.MainActivity">    <android.support.v4.view.ViewPager    android:id="@+id/vp"    android:layout_width="match_parent"    android:layout_height="match_parent"></android.support.v4.view.ViewPager>    <LinearLayout        android:id="@+id/ll"        android:gravity="center"        android:layout_alignParentBottom="true"        android:orientation="horizontal"        android:layout_width="match_parent"        android:layout_height="wrap_content">    </LinearLayout></RelativeLayout>
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.util.Log;import android.widget.ImageView;import android.widget.LinearLayout;import com.google.gson.Gson;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {    private Handler handler=new Handler(){        @Override        public void handleMessage(Message msg) {            super.handleMessage(msg);            int mum = msg.what;           switch (mum){               case 0:                   String json = (String) msg.obj;                   Log.e("============","handleMessage_json:"+json);                   parseData(json);                   break;               case 1:                   //得到当前viewpager的索引                   int position = vp.getCurrentItem();                   //让当前的的viewpager加1                   position++;                   //给viewPager设置当前的索引                   vp.setCurrentItem(position);                   sendMsg();                   break;           }        }    };    private ViewPager vp;    private LinearLayout ll;    private List<DataBean.Adlist> adlist;    private ArrayList<ImageView> ivList;    private ImageView iv;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        new Thread(){            @Override            public void run() {                super.run();                String json = NetWorkUtils.getjson();                Message msg = new Message();                msg.obj=json;                msg.what=0;                handler.sendMessage(msg);            }        }.start();        vp = (ViewPager) findViewById(R.id.vp);        ll = (LinearLayout) findViewById(R.id.ll);    }    //解析json字符串    private void parseData(String json){        Gson gson = new Gson();        DataBean dataBean = gson.fromJson(json, DataBean.class);        //得到所有的数据        adlist = dataBean.data.adlist;        //把数据传到adapter里面        MyAdapter adapter = new MyAdapter(MainActivity.this,adlist);        vp.setAdapter(adapter);        //初始化点        initDot();        //让viewpager的索引默认的指在1000        vp.setCurrentItem(1000);        //自动轮播、        sendMsg();        //viewPager的监听事件        ViewPagerListener();    }    private void ViewPagerListener() {        vp.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {            @Override            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {            }            @Override            public void onPageSelected(int position) {                for(int x=0;x<ivList.size();x++){                    if(position%adlist.size()==x) {                       //证明点和图片是对应的，应该点是变红的                       ivList.get(position % adlist.size()).setImageResource(R.drawable.dot_focuable);                   }else{                       ivList.get(x).setImageResource(R.drawable.dot_normal);                   }                }            }            @Override            public void onPageScrollStateChanged(int state) {            }        });    }    /*    * 实现自动轮播    * */    private void sendMsg() {        handler.sendEmptyMessageDelayed(1,2000);    }    //初始化点    private void initDot() {        ivList = new ArrayList<>();        if(ivList!=null){            ivList.clear();        }        for(int x=0;x<adlist.size();x++){            iv = new ImageView(MainActivity.this);            if(x==0){                //第一张，让其原点进行选中状态                iv.setImageResource(R.drawable.dot_focuable);            }else{                iv.setImageResource(R.drawable.dot_normal);            }            LinearLayout.LayoutParams parmes = new LinearLayout.LayoutParams(20, 20);             //设置两个点之间的距离            parmes.setMargins(10,0,10,0);            ll.addView(iv,parmes);            ivList.add(iv);        }    }}
import java.io.BufferedReader;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;/** * Created by HQ on 2017/9/13. */public class NetWorkUtils {    static String path="http://www.meirixue.com/api.php?c=index&a=index";    private static ByteArrayOutputStream baos;    public static String getjson(){        try {            URL url = new URL(path);            HttpURLConnection connection = (HttpURLConnection) url.openConnection();            connection.setRequestMethod("GET");            connection.setConnectTimeout(5000);            int responseCode = connection.getResponseCode();            baos = new ByteArrayOutputStream();            if(responseCode==200){                InputStream inputStream = connection.getInputStream();                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream));                StringBuilder builder = new StringBuilder();                String stringTem="";                while((stringTem=bufferedReader.readLine())!=null){                    builder.append(stringTem);                }                String s = builder.toString();                return s;            }        } catch (MalformedURLException e) {            e.printStackTrace();        } catch (IOException e) {            e.printStackTrace();        }        return "";    }}
import java.util.List;/** * Created by HQ on 2017/9/13. */public class DataBean {    public Data data;    public  class Data{        public List<Adlist> adlist;    }    public class Adlist{        public String id;        public String img;    }}
import android.app.Application;import com.nostra13.universalimageloader.core.ImageLoader;import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;/** * Created by HQ on 2017/9/13. */public class MyApplication extends Application {    @Override    public void onCreate() {        super.onCreate();        ImageLoaderConfiguration configuration = new ImageLoaderConfiguration.Builder(this).build();        ImageLoader.getInstance().init(configuration);    }}
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;/** * Created by HQ on 2017/9/13. */public class MyAdapter extends PagerAdapter {    Context context;    List<DataBean.Adlist> adlist;    public MyAdapter(Context context, List<DataBean.Adlist> adlist) {        this.context =context;        this.adlist=adlist;    }    @Override    public int getCount() {        return Integer.MAX_VALUE;    }    @Override    public boolean isViewFromObject(View view, Object object) {        return view==object;    }    @Override    public void destroyItem(ViewGroup container, int position, Object object) {       container.removeView((View)object);        //super.destroyItem(container, position, object);    }    @Override    public Object instantiateItem(ViewGroup container, int position) {        ImageView iv = new ImageView(context);        //对图片进行缩放        iv.setScaleType(ImageView.ScaleType.FIT_XY);        ImageLoader.getInstance().displayImage(adlist.get(position%adlist.size()).img,iv);        container.addView(iv);        return iv;    }}

    //权限
<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="bbb.bwie.com.gson"><uses-permission android:name="android.permission.INTERNET"/>    <application        android:name=".MyApplication"        android:allowBackup="true" android:icon="@mipmap/ic_launcher"        android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"        android:supportsRtl="true" android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>