Pass events between classes

There are many tutes on the web on how to make interface elements, such as drop down menus, or accordion menus. The example Menu Class includes all the event listeners and functions. It invariably ends with the CLICK event function tracing some comment so you know it works. But no information on how to implement the Menu Class

So say you have a Main Document Class that instantiates a Menu Class. How can you pass the CLICK event back to the Main Document Class to do something with it?
As far as I can see, the Menu Class can build the menu but all the listeners and functions for it have to reside in the Main Document Class.
Or do you have to build a custom Class that extends the Event Class?