android音乐播放器实现（Service+BroadcastReceiver+Notification）

public interface IMusic {  
    public void moveon();//继续  
    public void pause();//暂停  
    public void stop();//停止  
    public void nextSong();//下一曲  
    public void lastSong();//上一曲  
}  

定义Application类，用于传递全局变量：

public class Mp3Application extends Application {
   
     
    public List<Song> songsList;//当前播放列表  
    public int songItemPos;//当前播放音乐在列表中的位置  
    public NotificationManager notManager;  
    public IMusic music;  
}  

定义Service类，用于控制音乐播放：
public class PlayerService extends Service {
   
     
    private MediaPlayer mp;  
    private Mp3Application application;  
    private List<Song> songs;  
    private int songItemPos;  

    @Override  
    public void onCreate() {  
        super.onCreate();  
        application = (Mp3Application) getApplication();  
        songs = application.songsList;  
    }  

    @Override  
    public IBinder onBind(Intent intent) {  
        play(songItemPos);  
        return new