Selecting a ListBoxItem when its inner ComboBox is focused

Question

I have a DataTemplate that will be a templated ListBoxItem, this DataTemplate has a ComboBox in it which when it has focus I want the ListBoxItem that this template represents to become selected, this looks right to me. but sadly enough it doesn't work =(

So the real question here is within a DataTemplate is it possible to get or set the value of the ListBoxItem.IsSelected property via a DataTemplate.Trigger?

<DataTemplate x:Key="myDataTemplate" 
              DataType="{x:Type local:myTemplateItem}">

 <Grid x:Name="_LayoutRoot">
     <ComboBox x:Name="testComboBox" />
 </Grid>

 <DataTemplate.Triggers>
     <Trigger Property="IsFocused" value="true" SourceName="testComboBox">
         <Setter Property="ListBoxItem.IsSelected" Value="true" />
     </Trigger>
 </DataTemplate.Triggers>

</DataTemplate>

<ListBox ItemTemplate="{StaticResource myDataTemplate}" />

Answer 1

I found that I preferred to use this:

<Style  TargetType="ListBoxItem">
    <Style.Triggers>
        <Trigger Property="IsKeyboardFocusWithin" Value="True">
             <Setter Property="IsSelected" Value="True"></Setter>
        </Trigger>
    </Style.Triggers>
</Style>

Simple and works for all the listboxitems, regardless of what's inside.