AsyncTask网络请求数据

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MainActivity
package com.example.week2_lianxi;import android.os.AsyncTask;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.ListView;import com.example.Bean.Bean;import com.example.adapter.Myadapter;import org.json.JSONArray;import org.json.JSONObject;import java.io.ByteArrayOutputStream;import java.io.InputStream;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.util.ArrayList;public class MainActivity extends AppCompatActivity {    private ListView lv;    private ArrayList<Bean> list;    private Myadapter ma;    private String url="http://v3.wufazhuce.com:8000/api/reading/index/?version=3.5.0&platform=android";    private OneDAO dao;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        dao = new OneDAO();        initDate();        new MyAsyncTask().execute(url);    }    /**     * 初始化数据     */    private void initfinsh() {        ma = new Myadapter(this,list);        lv.setAdapter(ma);    }    private void initDate() {        ma = new Myadapter(this,list);    }    private void initView() {        lv= (ListView) findViewById(R.id.lv);        list= new ArrayList<Bean>();    }    class MyAsyncTask extends AsyncTask<String,String,String>    {        @Override        protected String doInBackground(String... strings) {            try {                URL url2=new URL(strings[0]);                HttpURLConnection connection= (HttpURLConnection) url2.openConnection();                connection.connect();                if(200==connection.getResponseCode())                {                    InputStream inputStream = connection.getInputStream();                    ByteArrayOutputStream baos=new ByteArrayOutputStream();                    int len=0;                    byte[] buffer=new byte[1024];                    while ((len=inputStream.read(buffer))!=-1)                    {                         baos.write(buffer,0,len);                    }                    String result = baos.toString();                    JSONObject obj=new JSONObject(result);                    JSONObject data = obj.getJSONObject("data");                    JSONArray dataArray = data.getJSONArray("serial");                    if(dataArray!=null&dataArray.length()>0)                    {                        for (int i = 0; i < dataArray.length(); i++) {                             Bean bean=new Bean();                             JSONObject data1= (JSONObject) dataArray.get(i);                             bean.title=data1.getString("title");                             bean.excerpt=data1.getString("excerpt");                             list.add(bean);                        }                        for (int j = 0; j < list.size(); j++) {                             dao.add(list.get(j).title,list.get(j).excerpt);                        }                    }                }            } catch (Exception e) {                e.printStackTrace();            }            return null;        }        @Override        protected void onPreExecute() {            super.onPreExecute();        }        @Override        protected void onPostExecute(String s) {            super.onPostExecute(s);            initfinsh();        }        @Override        protected void onProgressUpdate(String... values) {            super.onProgressUpdate(values);        }    }}

Adapter

package com.example.adapter;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.TextView;import com.example.Bean.Bean;import com.example.week2_lianxi.MainActivity;import com.example.week2_lianxi.R;import java.util.ArrayList;public class Myadapter extends BaseAdapter{    private Context context;    private ArrayList<Bean> bean;    public Myadapter(Context context, ArrayList<Bean> bean) {        this.context=context;        this.bean=bean;    }    @Override    public int getCount() {        return bean.size();    }    @Override    public Object getItem(int i) {        return bean.get(i);    }    @Override    public long getItemId(int i) {        return i;    }    @Override    public View getView(int i, View converView, ViewGroup viewGroup) {        ViewHolder holder=null;        if(converView==null)        {            holder=new ViewHolder();            converView= LayoutInflater.from(context).inflate(R.layout.item_lv, null);            holder.tv_title =(TextView) converView.findViewById(R.id.tv_title);            holder.tv_excerpt=(TextView) converView.findViewById(R.id.tv_excerpt);            converView.setTag(holder);        }else        {            holder = (ViewHolder) converView.getTag();        }        holder.tv_title.setText(bean.get(i).title);        holder.tv_excerpt.setText(bean.get(i).excerpt);        return converView;    }    public class ViewHolder    {        public TextView tv_title,tv_excerpt;    }}

Bean
package com.example.Bean;public class Bean {    public String title;    public String excerpt;}


item_lv布局
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:orientation="vertical"    android:layout_height="match_parent">    <TextView        android:id="@+id/tv_title"        android:layout_width="match_parent"        android:layout_height="wrap_content" />    <TextView        android:id="@+id/tv_excerpt"        android:layout_width="match_parent"        android:layout_height="wrap_content" /></LinearLayout>


Main布局
<?xml version="1.0" encoding="utf-8"?><LinearLayout 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="match_parent"   >    <ListView        android:id="@+id/lv"        android:layout_width="match_parent"        android:layout_height="match_parent"></ListView></LinearLayout>
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