Listbox
A listbox displays a choice of strings. It must be the child of a panel.
In a single-selection listbox, only one choice may be highlighted. In a
multiple-selection listbox, several may be highlighted.
list-box-create
list-box-append
list-box-find-string
list-box-clear
list-box-get-selection
list-box-get-string-selection
list-box-set-selection
list-box-set-string-selection
list-box-number
list-box-delete
list-box-get-string
list-box-get-first-selection
list-box-get-next-selection