Put a XamComboEditor in a XamGrid templatecolumn like:

<ig:TemplateColumn Key="Organization" HorizontalContentAlignment="Stretch" Width="320">
    <ig:TemplateColumn.HeaderTemplate>
        <DataTemplate>
            <TextBlock Text="{Binding GridHeaderStrings.Name, Source={StaticResource ResourceWrapper}}" />
        </DataTemplate>
    </ig:TemplateColumn.HeaderTemplate>
    <ig:TemplateColumn.ItemTemplate>
        <DataTemplate>
            <StackPanel Orientation="Vertical">
                <TextBlock x:Name="NameDisplay" Text="{Binding MyEntity.ID,Converter={StaticResource IDToNameConverter}}" HorizontalAlignment="Stretch" />
            </StackPanel>
        </DataTemplate>
    </ig:TemplateColumn.ItemTemplate>
    <ig:TemplateColumn.EditorTemplate>
        <DataTemplate>
            <ig:XamComboEditor x:Name="MyEntityEditList" IsEditable="False"
         SelectedItem="{Binding MyEntity, Mode=TwoWay}" Width="310">
                <ig:XamComboEditor.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Vertical">
                            <TextBlock Text="{Binding ID,Converter={StaticResource IDToNameConverter}}" Margin="5" VerticalAlignment="Center" />
                        </StackPanel>
                    </DataTemplate>
                </ig:XamComboEditor.ItemTemplate>
            </ig:XamComboEditor>
        </DataTemplate>
    </ig:TemplateColumn.EditorTemplate>
</ig:TemplateColumn>

Set up ItemSource for XamComboEditor in CellEnteredEditMode event of XamGrid. I have a few problem with XamComboEditor in this case:

1. When users choose one item from popup dropdown with mouse, then click on another other control out XamGrid, the selection will not be accepted. In order to fix this problem, I need to advise users: select one item from dropdown, then hit Tab key, then do something else.

2. I want to change XamComboEditor to be editable in this case by adding:

IsEditable="true"  AllowFiltering="True"

then run the app, the app is crashed with cascade exception.

How to fix the problem for this case?