I know i can play an mp3 file in the media player like that:
Intent intent = new Intent();
intent.setAction(android.content.Intent.ACTION_VIEW);
File fil
If you just need to set the sound URI on the Notification.Builder, use
Uri.parse("android.resource://com.my.great.application/"
+ R.raw.mysound);
where R.raw.mysound
can be something like mysoud.ogg
in the raw resources folder.
However I am not sure if MP3 is exactly supported. As these are just internal resources of your application, try to convert to OGG.