Not sure if you question was answered with the other post.
Whereas if you are going to simply play a sequence of tracks. The quick start is a good place along with the use of MP3player.isPlaying() function as to tell when a track is finished. Where something like the below would be a quick attempt to play track000.mp3 through track009.mp3
for (int n = 0; n < 9 ; n++)
{
MP3player.playTrack(key_command);
while (MP3player.isPlaying());
}