I am making my own customized Listbox. I am trying to include all the features of the listbox, such as Selected. However when my code in the application i am making the UserControl for, tries to set the List.Selected(Num) = False, I get an error "Assignment to a constant not permitted". Here is the code i have in the user control. What do i need to change or add to make it settable as well as readable?

Public Function Selected(Num As Integer) As Boolean
Selected = List1.Selected(Num)
End Function