Binding the property from the grandson level

[Trump]

Let's say I have a RadGridView ---first level.(Father)

Then Inside it there is RowDetails DataTemplate in each row  -- second level(Son)

Inside RowDetails template there is also a RadGridView, --- third level. (Grandson)

So in the cell template of the third level, I have a combobox, the itemsSource comes from ViewModel. So how to bind it? 

[Dinko | Tech Support Engineer]

Hi Trump,

What you could try is using RelativeSource to bind to the DataContext of the Window which holds the RadGridView (Father). You can set the DataContext of the Window to ViewModel. Then you can bind the RadComboBox inside a CellEditTemplate to your custom collection from the ViewModel using RelativeSource binding.

<telerik:RadGridView x:Name="GrandSon_GridView" ItemsSource="{Binding SonGridView_Collection}" >
    <telerik:RadGridView.Columns>
        <telerik:GridViewDataColumn Width="200">
            <telerik:GridViewDataColumn.CellEditTemplate>
                <DataTemplate>
                    <telerik:RadComboBox ItemsSource="{Binding DataContext.ComboBoxSource,RelativeSource={RelativeSource AncestorType=Window,Mode=FindAncestor}}"/>
                </DataTemplate>
            </telerik:GridViewDataColumn.CellEditTemplate>
        </telerik:GridViewDataColumn>
    </telerik:RadGridView.Columns>
</telerik:RadGridView>

Give this approach a try and let me know how it goes.

Regards,
Dinko
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