更新Adapter中的数据，并通知ListView显示

单击界面上的按钮，即可调用Adapter的notifyDatasetChanged()方法通知ListView更新显示。
实例：

package com.laili.apater;

import java.util.ArrayList; 
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;

public class ListAdapterActivity extends Activity {
   
	private ListView list;
	private ArrayAdapter<String> adapter;
	private ArrayList<String> data;
	private Button addBtn;
	private int i = 0;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        list = (ListView) findViewById(R.id.list);
        data = new ArrayList<String>();
        for (i = 0; i < 5; i++) {
        	data.add(new String("" + (i + 1)));
        }
        
        adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, data);
        list.setAdapter(adapter);
        
        
        addBtn = (Button) findViewById(R.id.add);
        addBtn.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				System.out.println(i);
				data.add(new String("" + (++i)));
				System.out.println(i);
				adapter.notifyDataSetChanged();
			}
		});
        
    }
}

布局：

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

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />
	<ListView 
	    android:id="@+id/list"
	    android:layout_width="fill_parent"
	    android:layout_height="wrap_content"
	    android:layout_weight="1"/>
	<Button 
	    android:id="@+id/add"
	    android:layout_width="fill_parent"
	    android:layout_height="wrap_content"
	    android:text="添加"/>
</LinearLayout>

显示效果：