listview的动态刷新主要是调用adapter的notifyDataSetChanged。
在下面的例子中除了记录正常的刷新外，还记录一种错误的情况（注释掉的），作为备忘。
notifyDataSetChanged除了数据无改变时不起作用，当数据的引用变化时也不起作用。因此在下面那个用数组的例子里，listview不会更新。
package com.example.demo_dlv;import java.util.ArrayList;
import java.util.List;import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.widget.ArrayAdapter;
import android.widget.ListView;public class MainActivity extends Activity { private ListView lv;
/*private String[] strs = new String[] {
"first", "second", "third", "fourth", "fifth"
};*/
private List<String> list;
private static int i = 0;
private ArrayAdapter<String> adapter; private Handler handler = new Handler(){
public void handleMessage(Message msg) {
switch (msg.what) {
case 1:
/*List<String> list = new ArrayList<String>();
for (int i=0; i<strs.length; i++) {
if(!list.contains(strs[i])) {
list.add(strs[i]);
}
} list.add("new Element" + i++);*/
list.add("item" + i++); System.out.println(list.size()); //strs = (String[]) list.toArray(new String[1]); 引用变了，无法动态刷新 adapter.notifyDataSetChanged();
break;
}
super.handleMessage(msg);
}
}; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); lv = (ListView) findViewById(R.id.lv); list = new ArrayList<String>();
list.add("item1");
list.add("item2");
list.add("item3");
list.add("item4");
list.add("item5"); adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, list);
lv.setAdapter(adapter); MyThread mt = new MyThread();
new Thread(mt).start();
} class MyThread implements Runnable{ @Override
public void run() {
int i = 0;
while(i < 3){
try {
Thread.sleep(3000);
Message message = new Message();
message.what = 1;
handler.sendMessage(message);
i++;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
