How to initialize main window objects from custom class during program start?

I have a main window with a couple of popupbuttons. I want to clear them, then load the lists from a method in a custom class. I've got my view controller working and I know the method in the custom class (newRequest) is working because I added a NSLog command to print "Test" when the method executes. In AppDelegate I'm calling the method via: [polyAppRequest newRequest];. As I said, I know the method is executing. Why can't I removeallitems from the popupbutton from this custom class method? Thanks Keith