一个完整的Android ListView+网络接口读取+JSON处理的Demo

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package cn.eoe.shuhai.eoethread;

import java.io.BufferedInputStream;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;

import org.apache.http.util.ByteArrayBuffer;
import org.apache.http.util.EncodingUtils;
import org.json.JSONArray;
import org.json.JSONObject;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.Gravity;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

    private ListView lv = null;
    private TextView tv = null;
    private ArrayList<String> lvList = new ArrayList<String>();
    private String more_url = null;
    private String urlContent = null;

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

        new Thread(runnable).start();

        tv = (TextView) findViewById(R.id.tv);
        tv.setText(" loading...");
    }

    Handler handler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            Bundle data = msg.getData();
            String content = data.getString("content");

            //尝试读取第二个页面的页面
            urlContent = url_get_content(more_url);

            //给一个弹出层拽一把
            Toast toast = Toast.makeText(getApplicationContext(), more_url, Toast.LENGTH_LONG);
            toast.setGravity(Gravity.CENTER, 0, 0);//居中显示
            toast.show();

            //准备一个list用来存放json数组中的数据
            lvList = json_decode(content);

            //将数组通过 adapter传递给控件
            ArrayAdapter<String> adapter = new ArrayAdapter<String>(MainActivity.this,
                    android.R.layout.simple_dropdown_item_1line,
                    lvList);

            //隐藏默认的提示内容
            tv.setHeight(0);

            //ListView加载刚刚的List
            lv = (ListView) findViewById(R.id.lv);
            lv.setAdapter(adapter);

        }
    };

    Runnable runnable = new Runnable() {
        @Override
        public void run()
        {
            more_url = more_url != null ? more_url : "http://api.eoe.cn/client/blog?k=lists&t=top";
            urlContent = url_get_content(more_url);

            Message msg = new Message();
            Bundle data = new Bundle();
            data.putString("content", urlContent);
            msg.setData(data);
            handler.sendMessage(msg);
        }
    };

    public static String url_get_content(String url) {
        String myString = null;
        try {
            // 定义获取文件内容的URL
            URL myURL = new URL(url);
            // 打开URL链接
            URLConnection ucon = myURL.openConnection();
            // 使用InputStream，从URLConnection读取数据
            InputStream is = ucon.getInputStream();
            BufferedInputStream bis = new BufferedInputStream(is);
            // 用ByteArrayBuffer缓存
            ByteArrayBuffer baf = new ByteArrayBuffer(50);
            int current = 0;
            while ((current = bis.read()) != -1) {
                baf.append((byte) current);
            }
            // 将缓存的内容转化为String,用UTF-8编码
            myString = EncodingUtils.getString(baf.toByteArray(), "UTF-8");
        } catch (Exception e) {
            // myString = e.getMessage();
            myString = null;
        }

        return myString;
    }

    /**
     * 格式化json的结果，只取items的数组
     * @param content
     * @return
     */
    public ArrayList<String> json_decode(String content)
    {
        //准备一个list用来存放json数组中的数据
        if(lvList == null)
        {
            ArrayList<String> lvList = new ArrayList<String>();
        }

        try {
            JSONObject josnObject = new JSONObject(content);
            JSONArray array = josnObject.getJSONObject("response").getJSONArray("items");

            //获取分页url
            more_url = josnObject.getJSONObject("response").getString("more_url");

            int length = array.length();

            for (int i = 0; i < length; i++) {
                JSONObject object = array.getJSONObject(i);
                lvList.add(object.getString("title").toString());
            }
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }

        return lvList;
    }
}