*/
public void setListAdpter(List mp3Infos) {
List<HashMap<String, String>> mp3list = 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("title", mp3Info.getTitle());
map.put("Artist", mp3Info.getArtist());
map.put("duration", String.valueOf(mp3Info.getDuration()));
map.put("size", String.valueOf(mp3Info.getSize()));
map.put("url", mp3Info.getUrl());
mp3list.add(map);
}
mAdapter = new SimpleAdapter(this, mp3list,
R.layout.music_list_item_layout, new String[] { "title", "Artist", "duration" },
new int[] { R.id.music_title, R.id.music_Artist, R.id.music_duration });
mMusiclist.setAdapter(mAdapter);
}
实现效果如图：
需求2：点击列表的每一项，启动一个服务来播放音乐
1. 注册条目点击监听器OnItemClickListener
2. 定义一个实现OnItemClickListener接口的内部类
3. 定义一个继承Service的服务类PlayerServie
1. 注册条目点击监听器OnItemClickListener
mMusiclist = (ListView) findViewById(R.id.music_list);
mMusiclist.setOnItemClickListener(new MusicListItemClickListener());
mp3Infos = getMp3Infos();
setListAdpter(getMp3Infos());
2. 定义一个实现OnItemClickListener接口的内部类
private class MusicListItemClickListener implements OnItemClickListener {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
if(mp3Infos != null) {
Mp3Info mp3Info = mp3Infos.get(position);
Log.d("mp3Info-->", mp3Info.toString());
Intent intent = new Intent();
intent.putExtra("url", mp3Info.getUrl());
intent.putExtra("MSG", AppConstant.PlayerMsg.PLAY_MSG);
intent.setClass(MainActivity.this, PlayerService.class);
startService(intent); //启动服务
}
}
}
3. 定义一个继承Service的服务类PlayerServie（未完善的Service类）
package com.wwj.sb.service;
import android.annotation.SuppressLint;
import android.app.Service;
import android.content.Intent;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.IBinder;
import com.wwj.sb.domain.AppConstant;
@SuppressLint("NewApi")
public class PlayerService extends Service {
private MediaPlayer mediaPlayer = new MediaPlayer(); //媒体播放器对象
private String path; //音乐文件路径
private boolean isPause; //暂停状态
@Override
public IBinder onBind(Intent arg0) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
if(mediaPlayer.isPlaying()) {
stop();
}
path = intent.getStringExtra("url");
int msg = intent.getIntExtra("MSG", 0);
if(msg == AppConstant.PlayerMsg.PLAY_MSG) {
play(0);
} else if(msg == AppConstant.PlayerMsg.PAUSE_MSG) {
pause();
} else if(msg == AppConstant.PlayerMsg.STOP_MSG) {
stop();
}
return super.onStartCommand(intent, flags, startId);
}
/**
-
播放音乐
-
@param position
*/
private void play(int position) {
try {
mediaPlayer.reset();//把各项参数恢复到初始状态
mediaPlayer.setDataSource(path);
mediaPlayer.prepare(); //进行缓冲
mediaPlayer.setOnPreparedListener(new PreparedListener(position));//注册一个监听器
}
catch (Exception e) {
e.printStackTrace();
}
}
/**
- 暂停音乐
*/
private void pause() {
if (mediaPlayer != null && mediaPlayer.isPlaying()) {
mediaPlayer.pause();
isPause = true;
}
}
/**
- 停止音乐
*/
private void stop(){
if(mediaPlayer != null) {
mediaPlayer.stop();
try {
mediaPlayer.prepare(); // 在调用stop后如果需要再次通过start进行播放,需要之前调用prepare函数
} catch (Exception e) {
e.printStackTrace();
}
}
}
@Override
public void onDestroy() {
if(mediaPlayer != null){
mediaPlayer.stop();
mediaPlayer.release();
}
}
/**
-
实现一个OnPrepareLister接口,当音乐准备好的时候开始播放
*/
private final class PreparedListener implements OnPreparedListener {
private int positon;
public PreparedListener(int positon) {
this.positon = positon;
}
@Override
public void onPrepared(MediaPlayer mp) {
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