Giving a WPF ItemsControl a different look based off whether ItemsSource holds a single value or multiple values?

Question

Are there any slick ways to style/template a WPF ItemsControl differently based off whether ItemsSource holds a single value or multiple values?

What I've done so far is to create a custom ItemsControl class which among other things displays the list of bound items as a horizontally oriented comma separated list. So far I'm pretty happy with the results however I want to show a more brief view of the bound data in cases where multiple values are bound and if only a single value is bound then I want to show a more extended view of the bound data with a longer string description. I figure this is probably best solved by dynamically choosing the template either based off a trigger or possibly by using a template selector but it's not yet clear to me how this would be done.

Answer 1

You could use a DataTrigger in your style to replace the template:

<Style.Triggers>
    <DataTrigger Binding="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=Items.Count}" Value="1">
        <Setter Property="Template">
            <Setter.Value>
                <!-- Insert Template here -->
            </Setter.Value>
        </Setter>
    </DataTrigger>
</Style.Triggers>

You could also add one for where the Value is 0 if you wanted to display a "no records" template.

Answer 2

You should use a StyleSelector. Here is a sample.