请求网络加载ListView Asynctack后台线程

MainActivity里的方法参数看一下代码：

import android.graphics.Bitmap;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import com.google.gson.Gson;

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

public class MainActivity extends AppCompatActivity {
public String urlString="http://api.expoon.com/AppNews/getNewsList/type/1/p/1";
    String urlBitmap="https://img-my.youkuaiyun.com/uploads/201407/26/1406383265_8550.jpg";
    private ListView li;
    private List<Javabing.DataBean> list;
    private MybaseAdapter mb;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        li = (ListView) findViewById(R.id.li);
        new Myasy().execute(urlString);
        list = new ArrayList<Javabing.DataBean>();
        Myasy my=new Myasy();
        mb = new MybaseAdapter();
        li.setAdapter(mb);
        my.execute(urlString);
    }
    private class Myasy extends AsyncTask<String,Void,String>{

        @Override
        protected String doInBackground(String... strings) {
            String str=strings[0];
            String json = Netutil.getJson(str);
            return json;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            Gson gson=new Gson();
            Javabing ja = gson.fromJson(s, Javabing.class);
            List<Javabing.DataBean> data = ja.getData();
            list.addAll(data);
            mb.notifyDataSetChanged();
        }
    }
  class MybaseAdapter extends BaseAdapter{

      @Override
      public int getCount() {
          return list.size();
      }

      @Override
      public Object getItem(int i) {
          return list.get(i);
      }

      @Override
      public long getItemId(int i) {
          return i;
      }

      @Override
      public View getView(int i, View view, ViewGroup viewGroup) {
          View vi = view.inflate(MainActivity.this, R.layout.two, null);
          TextView te = vi.findViewById(R.id.te);
          te.setText(list.get(i).getNews_summary());
          ImageView im = vi.findViewById(R.id.im);
           new MyAsynctask(im).execute(urlBitmap);
          return vi;
      }
  }
  private class MyAsynctask extends AsyncTask<String,Void,Bitmap>{
      private ImageView im;

      public MyAsynctask(ImageView im) {
          this.im=im;
      }

      @Override
      protected Bitmap doInBackground(String... strings) {
          return  Netutil.getNetBitmap(strings[0]);
      }

      @Override
      protected void onPostExecute(Bitmap bitmap) {
          super.onPostExecute(bitmap);
         im.setImageBitmap(bitmap);
      }
  }
工具包Utils里的方法，如一下代码： 

public static String getJson(String urlString){
    try {
        URL url=new URL(urlString);
        HttpURLConnection ur = (HttpURLConnection) url.openConnection();
        int responseCode = ur.getResponseCode();
         if (responseCode==200){
             InputStream inpu = ur.getInputStream();
             BufferedReader br=new BufferedReader(new InputStreamReader(inpu));
             StringBuffer sb=new StringBuffer();
             String line=null;
             while ((line=br.readLine())!=null){
                 sb.append(line);
             }
             return sb.toString();
         }
    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return "";
}
public static Bitmap getNetBitmap(String urlString){
    try {
        URL url=new URL(urlString);
        HttpURLConnection ur = (HttpURLConnection) url.openConnection();
        int re = ur.getResponseCode();
        if (re==200){
            InputStream inputStream = ur.getInputStream();
            Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
            return bitmap;
        }
    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}
然后自己在封装一个Javabing，用来解析Gson串,
中间适配器也需要XML文件，手动建造即可。