GetSelection
Getting the selected strings from a listbox or popup-menu is a standard job, which was performed by Matlab's POPUPSTR command until it became obsolete. Although this requires some lines of code only, considering single and multiple selections for listboxes is not completely trivial.

Therefore this small and simple function might be useful.

EXAMPLE:
Selected = GetSelection(UIHandle)
A string is replied for single selection listboxes and popup strings, a cell string for multi-selection listboxes.