使用AsyncTask+HttpClient_android asynctask+httpclient

package com.example.slx.slx12_27_01;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ListView;

import com.google.gson.Gson;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;

import java.util.List;

public class MainActivity extends AppCompatActivity {

    private ListView listview;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        listview = findViewById(R.id.listView);
        MyTask myTask = new MyTask();
        myTask.execute("http://api.tianapi.com/huabian/?key=48a7d7193e11bd2dd4a683b6e2f90a4f&num=10");

    }

    public class MyTask extends AsyncTask<String,Void,String> {

        @Override
        protected String doInBackground(String... strings) {
            HttpClient defaultHttpClient = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(strings[0]);
            try {
                HttpResponse response = defaultHttpClient.execute(httpGet);
                int statusCode = response.getStatusLine().getStatusCode();
                if(statusCode==200){
                    HttpEntity entity = response.getEntity();
                    String s = EntityUtils.toString(entity);
                    return s;
                }

            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            if(s!=null){
                Gson gson = new Gson();
                ResultData resultData = gson.fromJson(s, ResultData.class);
                List<ResultData.NewslistBean> newslist = resultData.getNewslist();

                MyAdapter myAdapter = new MyAdapter(MainActivity.this,newslist);
                listview.setAdapter(myAdapter);
            }
        }
    }
}


package com.example.slx.slx12_27_01;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;

/**
 * Created by lenovo on 2017/12/28.
 */

public class MyAdapter extends BaseAdapter{
    private Context context;
    private List<ResultData.NewslistBean> newslist;

    public MyAdapter(Context context, List<ResultData.NewslistBean> newslist) {
        this.context = context;
        this.newslist = newslist;
    }

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

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

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

    @Override
    public View getView(int i, View view, ViewGroup viewGroup) {
        ViewHolder holder;
        if(view==null){
            view=View.inflate(context,R.layout.item_list,null);
            holder=new ViewHolder();
            holder.textview=(TextView)view.findViewById(R.id.item_textview);
            holder.imageview=(ImageView)view.findViewById(R.id.item_image);
            view.setTag(holder);
        }else{
            holder=(ViewHolder) view.getTag();
        }
           holder.textview.setText(newslist.get(i).getTitle());
        MyPicTask myPicTask = new MyPicTask(holder.imageview);
        myPicTask.execute(newslist.get(i).getPicUrl());
        return view;
    }
    public class ViewHolder{
        TextView textview;
        ImageView imageview;
    }
    public class MyPicTask extends AsyncTask<String,Void,Bitmap>{
        private ImageView img;

        public MyPicTask(ImageView img) {
            this.img = img;
        }

        @Override
        protected Bitmap doInBackground(String... strings) {
            try {
            URL url = new URL(strings[0]);

                HttpURLConnection urlConnection = (HttpURLConnection)url.openConnection();
                urlConnection.setRequestMethod("GET");
                urlConnection.setReadTimeout(5000);
                urlConnection.setConnectTimeout(5000);
                int responseCode = urlConnection.getResponseCode();
                if(responseCode==200){
                    InputStream inputStream = urlConnection.getInputStream();
                    Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
                    return bitmap;
                }
            } catch (Exception e) {
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(Bitmap bitmap) {
            super.onPostExecute(bitmap);
            if(bitmap==null){
                img.setImageResource(R.mipmap.ic_launcher);
            }else {
                img.setImageBitmap(bitmap);
            }
        }
    }
}