Returns @true if any items were changed, i.e. if there had been any
selected items before, or @false if all the items were already deselected.
This method is only valid for multi selection listboxes.
Returns @true if any items were changed, i.e. if there had been any
selected items before, or @false if all the items were already deselected.
This method is only valid for multi selection listboxes.