Android HttpClient 网络获取数据

package com.bwei.httpclient.activity;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.Toast;

import com.bwei.httpclient.R;
import com.bwei.httpclient.adapter.MyAdapter;
import com.loopj.android.http.HttpGet;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;

import cz.msebera.android.httpclient.HttpResponse;
import cz.msebera.android.httpclient.client.HttpClient;
import cz.msebera.android.httpclient.impl.client.DefaultHttpClient;

public class MainActivity extends AppCompatActivity {
    String url = "http://120.27.23.105/ad/getAd";
    private ImageView iv;
    private ListView lv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //找控件
        iv = (ImageView) findViewById(R.id.iv);
        lv = (ListView) findViewById(R.id.lv);
        //创建异步任务
        // MyAsyncTask task = new MyAsyncTask();
        //执行异步任务
        // task.execute();

        //创建异步任务
        TwoAsyncTask twoAsyncTask = new TwoAsyncTask();
        //执行异步任务
        twoAsyncTask.execute(url);

    }

    /**
     * AsyncTask是异步任务，抽象类，实现线程之间通信，内部封装了handler+message+线程池
     * 定义一个类继承这个抽象类，重写它的抽象方法
     */

    public class MyAsyncTask extends AsyncTask<String, Integer, Bitmap> {

        /**
         * Params 参数
         * Progress 进度
         * Result 结果
         *
         * @param
         * @return
         */
        //onPreExecute这个方法运行在主线程，而且在doInBackground方法之前执行，做准备工作
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        //doInBackground这个方法运行在子线程，可以耗时操作
        @Override
        protected Bitmap doInBackground(String... params) {//可变参
            String url = "http://p2.so.qhimgs1.com/sdr/200_200_/t01aa0205686cc0182e.jpg";
            //在这个方法中做网络请求
            //创建一个网络请求对象 面向对象 父类引用指向子类的实现
            HttpClient client = new DefaultHttpClient();
            //创建get请求方式
            HttpGet get = new HttpGet(url);

            try {
                //网络请求对象执行请求 得到响应
                HttpResponse response = client.execute(get);
                //判断状态码
                if (response.getStatusLine().getStatusCode() == 200) {
                    //从服务器获取输入流
                    InputStream inputStream = response.getEntity().getContent();
                    Bitmap bitmap = BitmapFactory.decodeStream(inputStream);

                    return bitmap;

                }

            } catch (IOException e) {
                e.printStackTrace();
            }


            return null;
        }

        //onProgressUpdate这个方法运行在主线程，更新进度 ，这个方法在调用publishProgress()之后执行
        @Override
        protected void onProgressUpdate(Integer... values) {
            super.onProgressUpdate(values);

        }

        //onPostExecute这个方法运行在主线程，可以更新UI
        @Override
        protected void onPostExecute(Bitmap bitmap) {
            super.onPostExecute(bitmap);
            iv.setImageBitmap(bitmap);

        }
    }

    public class TwoAsyncTask extends AsyncTask<String, Integer, String> {

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            Toast.makeText(MainActivity.this, "在onPreExecute方法中做准备工作", Toast.LENGTH_SHORT).show();
        }

        @Override
        protected String doInBackground(String... params) {

            //在这个方法中做耗时操作
            //创建网络请求对象
            HttpClient client = new DefaultHttpClient();
            //创建请求方式
            String path = params[0];
            HttpGet get = new HttpGet(path);
            //网络请求对象执行请求
            try {
                HttpResponse response = client.execute(get);
                //判断状态码
                int code = response.getStatusLine().getStatusCode();
                if (code == 200) {
                    //从服务器获取输入流
                    InputStream inputStream = response.getEntity().getContent();
                    //定义一个字节数组输出流
                    ByteArrayOutputStream bos = new ByteArrayOutputStream();
                    //定义一个字节字节数组
                    byte[] buffer = new byte[1024];
                    //定义长度
                    int len = 0;
                    while ((len = inputStream.read(buffer)) != -1) {
                        bos.write(buffer, 0, len);
                    }
                    inputStream.close();
                    bos.close();
                    String json = bos.toString("utf-8");
                    return json;

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

        @Override
        protected void onProgressUpdate(Integer... values) {
            super.onProgressUpdate(values);
            Toast.makeText(MainActivity.this, "在onProgressUpdate方法中更新进度", Toast.LENGTH_SHORT).show();
        }

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            Log.i("xxx", s);
            try {
                //原生获取对象
                JSONObject jsonObject = new JSONObject(s);
                //原生获取集合
                JSONArray data = jsonObject.getJSONArray("data");
                //创建适配器 并构造传参
                MyAdapter adapter = new MyAdapter(MainActivity.this, data);
                //设置适配器
                lv.setAdapter(adapter);

            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
    }
}