Using a ListBox control in a DataTemplate

I have a simple WP7 Programm where I want to switch between displaying my model objects in a ListBox and a Diagramm.

I want to use Data Templates and a Selector Class which returns the correct template. The selector takes a boolean property in the view model and returns ListBoxTemplate or DiagrammTemplate

My Page Resources looks like this:

      <local:NewTemplateSelector x:Key="NewTemplateSelector">
        <local:NewTemplateSelector.ListBoxTemplate>        
                <DataTemplate>
                <StackPanel>
                    <ListBox  
                 x:Name="MainListBox" Margin="6,205,35,136"  ItemsSource="{Binding Acts}"                        
                    ItemTemplate="{Binding ElementName=Page, Path=Orientation, 
                    Converter={StaticResource OrientationToListItemTemplate}}" />                                                       
                </StackPanel>
            </DataTemplate>

        </local:NewTemplateSelector.ListBoxTemplate>

        <local:NewTemplateSelector.DiagrammTemplate>
            <DataTemplate>
                <TextBlock Text="Diagramm"/>
   开发者_开发百科         </DataTemplate>
        </local:NewTemplateSelector.DiagrammTemplate>

    </local:NewTemplateSelector>

My content Panel has only 1 element:

 <ContentControl ContentTemplate="{Binding IsDiagramm, 
    Converter={StaticResource NewTemplateSelector}}" HorizontalAlignment="Left" HorizontalContentAlignment="Left" />

I always get a blank screen when I run this. My Selector class returns the correct template, I can see this in the debugger. When I replace the Listbox in the template with a simple textblock, the textblock is displayed, so I suspect a problem with databinding.

But the listbox in the template works fine, when I insert it in my content panel without any data templates.

Any hints for me?

You may like to refer to this thread which discusses nested listboxes.

Listbox Inside listbox Databinding Problem