Gets or sets the orientation of items within groups. This is a dependency property.
One of the Orientation enumeration values.
Groups use specific container panels to arrange their items. Use the ItemsPanelOrientation property to control the manner in which items are stacked within these panels. By default, items are oriented vertically. Note that you can define a custom container panel by using the NavBarViewBase.ItemsPanelTemplate property.
To learn more, see the View Layout Customization topic.