如果您要在设备上启动默认的音乐播放器应用，请尝试以下操作:

If you would like to start the default music player app on the device, should try this:

Intent intent = new Intent();  
intent.setAction(android.content.Intent.ACTION_VIEW);  
File file = new File(YOUR_SONG_URI);  
intent.setDataAndType(Uri.fromFile(file), "audio/*");  
startActivity(intent);