The toolbar’s delegate object.
The delegate should conform to the
UIToolbarDelegate protocol. You may not set the delegate when the toolbar is managed by a navigation controller. The default value is
Managing Toolbar Changes
UIToolbarDelegate protocol defines the interface that toolbar delegate objects implement to manage the toolbar behavior. This protocol declares no methods of its own but conforms to the
UIBarPositioningDelegate protocol to support the positioning of a toolbar when it is moved to a window.