MVVM, RowDetailsTemplate,

[Sadaf]

Hi,
I have spent lot of time on it but no joy.
I am using radgridview with MVVM but I can't find a way to populate data in the rowdetailstemplate which has a gridview/user control in it basically I am doing exactly what you here: http://demos.telerik.com/silverlight/#GridView/FirstLook 

This is the main part I am interested in :  

Example.xaml:
...... 
<telerik:RadTabItem Header="Orders">
                            <local:OrdersView />
                        </telerik:RadTabItem>
                        <telerik:RadTabItem Header="Performance Chart" HorizontalContentAlignment="Stretch" HorizontalAlignment="Left">
                            <local:PerformanceChart />
                        </telerik:RadTabItem>
                    </telerik:RadTabControl>
                </DataTemplate> ......

The bold part I am interested in. 
LIMITATION.. I CAN'T USE ViewModel IN TE XAML BECAUSE I DO NOT HAVE THE DEFAULT CONSTRUCTOR FOR VIEW MODEL. 

The biding from this example does not work for me. How can achieve this..? Thanks so much.