MP3 Player Using XML Drop-Down Menu

I want to attempt to utilize the “XML Driven Drop Down Menu” available here on kirupa as a menu system for an XML MP3 player. I think I understand on some level what needs to be done. I fail to logically understand how to put it together.

The XML Drop Down Menu Tutorial in question easily offers a way to run a function from any of the menu items. The XML can contain variables that are passed to the functions. For anyone who has gone through that tutorial, you’ll understand. I may not entirely understand it though. I believe I do…

My intentions may not work out but I’m wondering if it could: I want the menu items to list categories. Upon clicking on a category/menu item it displays a list of MP3s. You can then choose an MP3 to play.

I’m wondering how I might most effectively go about this?

How should I alter the XML file for the Drop Down Menu?

Should there be an additional XML file for listing the audio and MP3s?

Could I simply create a function for the XML Drop Down Menu that could perform this task?

Thank you for any help.