Treeview Binding (With a 'Folder' between the bound Nodes) - wpf

Question

I have following problem with which I'm wrestling now for about 5 hours.
How do I correctly bind the following class structure to a TreeView?
public class Person
{
public string Display { get; set; }
public List<Car> Cars { get; set; }
public List<House> Houses { get; set; }
}
public class Car
{
public string Display { get; set; }
}
public class House
{
public string Display { get; set; }
}
I want the TreeView to have the following structure:
(Where Person #1 has both houses and cars, and Person #2 just has houses)
- Person #1
|-- Cars
|-- Car #1
|-- Car #2
|-- Houses
|-- House #1
- Person #2
|-- Houses
|-- House #1
|-- House #2
How on earth do you this in XAML with automatic Databinding to an ObservableCollection?
I set the binding only once in the Constructor of my Treeview (UserControl) like this:
this.ItemsSource = SomeStaticClass.People;
Help is very very much appreciated!
Thanks! =)
EDIT:
I tried the HierarchicalDataTemplate, but I can't get it to work ;)
EDIT2: I tried many many different things, but the closest I have come to is following code (with just one Enumeration in mind at this time ;)):
<HierarchicalDataTemplate DataType="{x:Type e:Person}" ItemsSource="{Binding Cars}">
<TextBlock Text="{Binding Display}" />
<HierarchicalDataTemplate.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Cars}">
<TextBlock Text="Cars" />
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Display}" />
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
Unfortunately, it doesn't display the TextBlock Cars and the Cars themself. How do I do that?

Answer 1

Finally solved.
I just inserted another Collection of classes between my Person and Car (resp. Home) like this:
public class CollectionHolder<T> : IEnumerable
{
public List<T> Items { get; set; }
public string Display { get; set; }
private List<CollectionHolder<T>> self;
public CollectionHolder()
{
self = new List<CollectionHolder<T>>();
self.add(this);
}
public IEnumerator GetEnumerator()
{
return self.GetEnumerator();
}
}
And than the Person class:
public class Person
{
public string Display { get; set; }
public CollectionHolder<Car> Cars { get; set; }
public CollectionHolder<House> Houses { get; set; }
public IList Children
{
get
{
return new CompositeCollection
{
new CollectionContainer { Collection = Cars },
new CollectionContainer { Collection = Houses }
});//In real world: don't generate the list everytime!
}
}
}
And finally my XAML:
<TreeView x:Name="trvData" Grid.Row="0" BorderThickness="0,0,0,1">
<TreeView.Resources>
<HierarchicalDataTemplate DataType="{x:Type e:Person}" ItemsSource="{Binding Children}">
<TextBlock Text="{Binding Display}" />
<HierarchicalDataTemplate.ItemTemplate>
<HierarchicalDataTemplate ItemsSource="{Binding Items}">
<TextBlock Text="{Binding Display}" />
<HierarchicalDataTemplate.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Display}" />
</DataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</HierarchicalDataTemplate.ItemTemplate>
</HierarchicalDataTemplate>
</TreeView.Resources>
</TreeView>