When a collection is provided for a given detail grid, it and the detail's SelectedItems collection will be synchronized at all times (in both directions). This allows the user to modify the list of selected items, or be notified of any change done in the selected items.
The collection must implement the IList interface, and must implement a notification interface, either INotifyCollectionChanged (recommended), or IBindingList.
Unlike the DataGridControl's SelectedItemsSource, here we use a dictionnary of collections, as there can be more than one detail attached to a single master item, and each detail has its own collection of SelectedItems.
A code example can be found in the MVVM sample.
Target Platforms: Windows 11, Windows, 10, Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2