A BarManager object.
Commands, submenus, static text, editors and other in-ribbon elements are represented by corresponding bar item objects. For these objects to be displayed within a RibbonControl and RibbonStatusBarControl, they first must be created within a BarManager object, which represents a storage of bar items. The RibbonControl and RibbonStatusBarControl must be children of this BarManager, i.e. must be declared in XAML between the BarManager start and end tags.
The Manager property is initialized automatically with the BarManager object that is the RibbonControl's parent.