cocoll 0 Junior Poster in Training

hello!
i am trying to merge to control a combobox and a listbox so when i click the arrow in combobox i want to overwrite the method in combobox so i can open a listbox when i click at the arrow.
so the first step it's to know all the property of a combobox and the listbox ,so the question is:
where i can found them?
thank you!:)