+/*
+ The numArg here is the listbox item index while the strArg is used
+ differently for the different actions:
+
+ a) for wxACTION_LISTBOX_FIND it has the natural meaning: this is the string
+ to find
+
+ b) for wxACTION_LISTBOX_SELECT and wxACTION_LISTBOX_EXTENDSEL it is used
+ to decide if the listbox should send the notification event (it is empty)
+ or not (it is not): this allows us to reuse the same action for when the
+ user is dragging the mouse when it has been released although in the
+ first case no notification is sent while in the second it is sent.
+ */