xlistview

第四步

MyAsyncTask 

package com.bawei.test.xlistview;

import android.content.Context;
import android.content.Intent;
import android.os.AsyncTask;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;

import com.google.gson.Gson;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.List;


public class MyAsyncTask   extends AsyncTask<String,Integer,String> {
    static DataBean mDatabean;
    Context con;
    String url;
    String type;
    ListView listView;
    public MyAsyncTask(Context con, String url, String type, ListView listView) {
        super();
        this.url=url;
        this.con=con;
        this.type=type;
        this.listView=listView;

    }

    //网络请求
    public void GetDatas(String murl, String mtype) {
        //头条服务器地址
        try {
            URL url = new URL(murl);
            //打开连接
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            //设置
            connection.setRequestMethod(mtype);
            connection.setConnectTimeout(5000);
            connection.setReadTimeout(5000);

            //post方式要提交参数给服务器...以流的方式提交给服务器
            connection.setDoOutput(true);
            //设置请求参数的类型
            //connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");

            String params = "key=8d6e3228d25298f13af4fc40ce6c9679&num=10";
            //参数以流的形式写给服务器...字节数组的形式写出去
            connection.getOutputStream().write(params.getBytes());

            //响应
            int responseCode = connection.getResponseCode();
            if (responseCode == 200) {
                //获取输入字节流
                InputStream inputStream = connection.getInputStream();

                String json = streamToString(inputStream, "utf-8");

                Log.i("json", json);
                //解析...解析完成之后发送到主线程,设置适配器
                Gson gson = new Gson();
                mDatabean = gson.fromJson(json, DataBean.class);
                Log.i("json", mDatabean.getCode());


            }


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

    }

    private String streamToString(InputStream inputStream, String charset) {
        try {
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream, charset);

            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
            String s = null;
            StringBuilder builder = new StringBuilder();
            while ((s = bufferedReader.readLine()) != null) {
                builder.append(s);
            }

            bufferedReader.close();
            return builder.toString();

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

        return null;
    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        List<DataBean.NewslistBean> listbean=mDatabean.getNewslist();
        //设置适配器
        MyAdapter myAdapter = new MyAdapter(listbean,con);
        listView.setAdapter(myAdapter);




    }

    public MyAsyncTask() {
        super();
    }

    @Override
    protected String doInBackground(String... strings) {
        GetDatas(url, type);
        return null;
    }
}