Listview分页加载

//=========主页面=============

package com.example.fenye;

import java.util.ArrayList;
import java.util.List;

import com.example.fenye.adapter.MyAdapter;
import com.example.fenye.bean.News;

import android.os.Bundle;
import android.os.Handler;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;

public class MainActivity extends Activity implements OnScrollListener {
   private List<News> news=new ArrayList<News>();

    private ListView lv;
   private View loadmoreView;
   private Button bt_loadmore;
   private int visibleLastIndex =0;//最后的可视项索引
   private int visibleItemCount;// 当前窗口可见项总数
   private int datasize=38;//模拟数据集的条数

   private Handler handler=new Handler();

   private MyAdapter adapter;

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


        //找到加载更多的布局
       loadmoreView = getLayoutInflater().inflate(R.layout.loadmore, null);
       //找到加载更多的控件
       bt_loadmore = (Button) loadmoreView.findViewById(R.id.bt_loadmore);
       //设置加载更多的监听
       bt_loadmore.setOnClickListener(new OnClickListener() {

       @Override
       public void onClick(View v) {
           bt_loadmore.setText("正在加载中...");//设置按钮文字
           //使用handler发送一个延迟消息
           handler.postDelayed(new Runnable() {

               @Override
               public void run() {
                   //加载更多数据
                   loadMoreData();
                   //刷新适配器
                   adapter.notifyDataSetChanged();
                   bt_loadmore.setText("查看更多...");//恢复按钮文字
               }


           }, 2000);


       }
   });
     //找到控件
       lv = (ListView) findViewById(R.id.lv);
       lv.addFooterView(loadmoreView);
       //初始化数据
       initializeAdapter();
       //设置适配器
       adapter = new MyAdapter(news, this);
       lv.setAdapter(adapter);
       lv.setOnScrollListener(this);
    }
   //加载更多数据
   private void loadMoreData() {
       int count=adapter.getCount();
       if (count+10<datasize) {
           for (int i = count+1; i <=count+10; i++) {
               News item=new News();
               item.setName("姓名："+i);
               adapter.addNewsItem(item);
           }
       }else{
           for (int i = count+1; i <datasize; i++) {
               News item=new News();
               item.setName("姓名："+i);
               adapter.addNewsItem(item);
           }
       }

   }

//初始化数据
    private void initializeAdapter() {
       for (int i = 0; i <=10; i++) {
           News newss=new News();
           newss.setName("姓名："+i);
           news.add(newss);
       }

   }

   //滑动监听
   @Override
   public void onScrollStateChanged(AbsListView view, int scrollState) {
       int itemsLaseIndex=adapter.getCount()-1;//数据集最后一项的索引
       int lastIndex=itemsLaseIndex+1;
       if (scrollState==OnScrollListener.SCROLL_STATE_IDLE&&visibleLastIndex==lastIndex) {
           // 如果是自动加载,可以在这里放置异步加载数据的代码
       }

   }
   //滑动监听
   @Override
   public void onScroll(AbsListView view, int firstVisibleItem,
           int visibleItemCount, int totalItemCount) {
       visibleItemCount=visibleItemCount;
       visibleLastIndex=firstVisibleItem+visibleItemCount-1;
       //如果所有的记录选项等于数据集的条数，则移除列表底部视图
       if (totalItemCount==datasize+1) {
           lv.removeFooterView(loadmoreView);
           Toast.makeText(this, "数据全部加载完！", 0).show();
       }
   }

}

//========创建一个MyAdapter 继承 BaseAdapter====================

package com.example.fenye.adapter;

import java.util.List;

import com.example.fenye.R;
import com.example.fenye.bean.News;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

public class MyAdapter extends BaseAdapter{
   private List<News> news;
   private Context context;


   public MyAdapter(List<News> news, Context context) {
       super();
       this.news = news;
       this.context = context;
   }

   @Override
   public int getCount() {
       // TODO Auto-generated method stub
       return news.size();
   }

   @Override
   public Object getItem(int position) {
       // TODO Auto-generated method stub
       return news.get(position);
   }

   @Override
   public long getItemId(int position) {
       // TODO Auto-generated method stub
       return position;
   }

   @Override
   public View getView(int position, View convertView, ViewGroup parent) {
       ViewHolder holder;
       News newss=news.get(position);
       if (convertView==null) {
           convertView=View.inflate(context, R.layout.list_item, null);
           holder=new ViewHolder();
           holder.name=(TextView) convertView.findViewById(R.id.tv_name);
           convertView.setTag(holder);
       }
       holder=(ViewHolder) convertView.getTag();
       holder.name.setText(newss.getName());
       return convertView;
   }
   static class ViewHolder{
       public TextView name;
   }
   public void addNewsItem(News newsitem){
       news.add(newsitem);
   }


}

//===========bean包==创建一个News类======================

package com.example.fenye.bean;

public class News {
   private String name;

   public News(String name) {
       super();
       this.name = name;
   }

   public News() {
       super();
   }

   public String getName() {
       return name;
   }

   public void setName(String name) {
       this.name = name;
   }

   @Override
   public String toString() {
       return "News [name=" + name + "]";
   }


}

//=============main布局文件 ==========================

//=========list_item布局文件======================

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

</LinearLayout>

//=========loadmore布局文件====================

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    <Button android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/bt_loadmore"
        android:text="查看更多..."/>

</LinearLayout>