上拉加载、下拉刷新功能实现

package com.example.my_xlistview_text;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.channels.GatheringByteChannel;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import com.example.adapter.MyAdapter;
import com.example.bean.BeanVO;
import com.example.fresh.XListView;
import com.example.fresh.XListView.IXListViewListener;
import com.google.gson.Gson;

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

public class MainActivity extends Activity implements IXListViewListener{
   private XListView xlv;
   private int flag=10;
   private List<String> list,initlist;
   private MyAdapter adapter;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //找控件

        xlv = (XListView) findViewById(R.id.xlv);
        //设置上拉下拉
        xlv.setPullRefreshEnable(true);
        xlv.setPullLoadEnable(true);
        xlv.setXListViewListener(this);
        list=new ArrayList<String>();
        initlist=new ArrayList<String>();
        adapter=new MyAdapter(list, this);
        xlv.setAdapter(adapter);
        //请求并解析数据
        new Thread(){
           public void run() {
               getdata();
           };
        }.start();

    }
/**
* 请求并解析数据
*/
    public void getdata(){
               //HttpClient请求数据
               HttpClient client=new DefaultHttpClient();
               HttpGet get=new HttpGet("http://op.juhe.cn/onebox/news/words?key=aadc8e1a325cd0b899e91639018d1769");
               try {
                   HttpResponse response = client.execute(get);
                   if (response.getStatusLine().getStatusCode()==200) {
                       //得到数据
                       Log.i("请求数据", "刷新");
                       InputStream is=response.getEntity().getContent();
                       BufferedReader reader=new BufferedReader(new InputStreamReader(is));
                       StringBuffer sb=new StringBuffer();
                       String str;
                       while ((str=reader.readLine())!=null) {
                           sb.append(str);
                       }
                       String jsonstr=sb.toString();
                       //Gson解析
                       Gson gson=new Gson();
                       BeanVO bv=gson.fromJson(jsonstr, BeanVO.class);
                       list = bv.getResult();
                       initdata();
                       //发送消息
                       Message msg=handler.obtainMessage(1, initlist);
                       handler.sendMessage(msg);

                   }
               } catch (ClientProtocolException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               } catch (IOException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               }
    }
/**
* 展示的条目数
*/
    public void initdata(){
       initlist.clear();
       if (list.size()>flag) {
           for (int i = 0; i < flag; i++) {
               initlist.add(list.get(i));
           }
       } else {
            initlist.addAll(list);
       }
    }
/**
* 处理消息
*/
    Handler handler=new Handler(){
       public void handleMessage(android.os.Message msg) {
           if (msg.what==1) {
               //得到传来的数据
               List<String> lists=(List<String>) msg.obj;
               //刷新适配器展示数据
               adapter.setNewData(lists);
           }
       };
    };

/**
* 下拉刷新
*/
@Override
public void onRefresh() {
   // TODO Auto-generated method stub
   //请求数据
   flag=10;
   new Thread(){
       public void run() {

       getdata();

       };
   }.start();
   onLoad();
}
/**
* 上拉加载
*/
@Override
public void onLoadMore() {
   // TODO Auto-generated method stub
           flag+=10;
           initdata();
           adapter.setNewData(initlist);
           onLoad();
           if (list.size()<flag) {
               Toast.makeText(MainActivity.this, "没有更多数据", 1000).show();
           }

}
/**
* 停止加载
*/
public void onLoad(){
   xlv.stopLoadMore();
   xlv.stopRefresh();
}
}

layout布局效果