Add behavior to RadioButton in ItemsControl (Windows 8 Search) - xaml

Question

I'm implementing the search contract (results page) of a Windows 8 application. I've designed everything to follow MVVM. With that, I'm trying to wire up a command to the 'filtersItemsControl' that is provided in the search contract template for Windows 8.
<ItemsControl
x:Name="filtersItemsControl"
Canvas.ZIndex="1"
ItemsSource="{Binding Source={StaticResource filtersViewSource}}"
Visibility="{Binding ShowFilters, Converter={StaticResource BooleanToVisibilityConverter}}"
Margin="120,-3,120,30">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<RadioButton
GroupName="Filters"
IsChecked="{Binding Active, Mode=TwoWay}"
common:CheckedCommandBehavior.Command="{Binding RelativeSource={RelativeSource Self}, Path=FilterChangedCommand}"
Style="{StaticResource TextRadioButtonStyle}">
<TextBlock Text="{Binding Description}" Margin="3,-7,3,10" Style="{StaticResource GroupHeaderTextStyle}" />
</RadioButton>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
The code above is my attempt to hook into 'FilterChangedCommand' which is a property of the ViewModel. The ViewModel also contains a list of properties that the ItemsControl is bound to (filtersViewSource). I think my issue is that I'm trying to bind the Command of the RadioButton to a property of filtersViewSource (which obviously does not exist) vs. the ViewModel.
So with that, I THINK the question here is basically, what binding expression can I used on the above RadioButton such that it will reference the ViewModel property.

Answer 1

FiltersViewSource should a property in viewmodel of some type, say "Foo". In that case, radio button will get datacontext of type Foo. So the property "FilterChangedCommand" should be in Foo class.