<avalon:DockingManager x:Name="DockManager"
                           Grid.Row="2"
                           BorderBrush="Black"
                           Margin="3"
                           Background="#FFFDFDFD"
                           BorderThickness="0"
                           AllowMixedOrientation="True"
                           DocumentsSource="{Binding Documents}"
                           AnchorablesSource="{Binding Anchorables}">