menuBackend, getValue & setValue ?

Afternoon all,

Does anyone know which values the getValue and setValue functions in the MenuBackend.h file refer to / can operate on ?

Is it just part of the menu "level system" or can you actually manipulate values in your menu "fields" ?

for example increment Mode "1" to Mode "2" just by using setValue rather than calling another menu called "Mode 2" ?
or just change a value without requiring another function dedicated just to changing that value ?

I can't find any docs or examples explaining these particular functions anywhere.

Thanks for any help,
Cheers,
mala