如何将mp3文件以列表的形式显示出来？

public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == UPDATE) {
updateListView();
} else if (item.getItemId() == ABOUT) {
// 用户点击了关于按钮
}
return super.onOptionsItemSelected(item);
}
private SimpleAdapter buildSimpleAdapter(List<Mp3Info> mp3Infos){
// 生成一个List对象，并按照SimpleAdapter的标准，将mp3Infos当中的数据添加到List当中去
List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>();
for (Iterator iterator = mp3Infos.iterator(); iterator.hasNext();) {
Mp3Info mp3Info = (Mp3Info) iterator.next();
HashMap<String, String> map = new HashMap<String, String>();
map.put("mp3_name", mp3Info.getMp3Name());
map.put("mp3_size", mp3Info.getMp3Size());
list.add(map);
}
// 创建一个SimpleAdapter对象
SimpleAdapter simpleAdapter = new SimpleAdapter(this, list,
R.layout.mp3info_item, new String[] { "mp3_name", "mp3_size" },
new int[] { R.id.mp3_name, R.id.mp3_size });
// 将这个SimpleAdapter对象设置到ListActivity当中
return simpleAdapter;
}
private void updateListView() {
// 用户点击了更新列表按钮
// 下载包含所有Mp3基本信息的xml文件
String xml = downloadXML("http://219.245.78.236:8080/mp3/resources.xml");
// 对xml文件进行解析，并将解析的结果放置到Mp3Info对象当中，最后将这些Mp3Info对象放置到List当中
List<Mp3Info> mp3Infos = parse(xml);
SimpleAdapter simpleAdapter = buildSimpleAdapter(mp3Infos);
setListAdapter(simpleAdapter);
}