Populates the target region with the views registered to it in the IRegionViewRegistry.
Defines a behavior that forwards the RegionContextProperty to the views in the region.
Defines the attached behavior that keeps the items of the Selector host control in synchronization with the IRegion. This behavior also makes sure that, if you activate a view in a region, the SelectedItem is set. If you set the SelectedItem or SelectedItems (ListBox) then this behavior will also call Activate on the selected items.