Custom control with several datatemplates/contentpresenters - wpf

Question

In a card game I need a control that shows a collection of 4 items (North, East, South and West) in a grid. The grid is 3x3 and it shows content in cells (0,1) (1,0) (1,2) and (2,1) respectively.
<bridge:SeatCollection ItemsSource="{Binding Path=Hands}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Vertical">
<TextBlock Text="{Binding Path=Name}" />
</StackPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</bridge:SeatCollection>
The above I have already working and is done by creating a control that inherits from ItemsControl and does something smart in GetContainerForItemOverride as described in another post on StackOverflow.
My question is how I can add another property to the control that contains the content that must be shown in the middle cell and how can the control render that content?
Using the control should be like:
<bridge:SeatCollection ItemsSource="{Binding Path=Hands}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=Name}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
<bridge:SeatCollection.MiddleCell>
<TextBlock Text="Content for middle cell"/>
</bridge:SeatCollection.MiddleCell>
</bridge:SeatCollection>
According to this article (http://www.ikriv.com/dev/wpf/displayingcontent/index.html) I can add a property and use that property in a ContentPresenter
public object MiddleCell
{
get { return (object)GetValue(MiddleContentProperty); }
set { SetValue(MiddleContentProperty, value); }
}
public static readonly DependencyProperty MiddleContentProperty =
DependencyProperty.Register("MiddleCell", typeof(object), typeof(SeatCollection), new PropertyMetadata(0));
But where and how in code can I add this content to my grid's middle cell?

Answer 1

I don't know what smart thing you're doing in GetContainerForItemOverride so I'll just ignore that part. Your bridge:SeatCollection is a custom control that derives from ItemsControl, correct? So it will have a default style defined in Themes\Generic.xaml. Change that style so it has a ContentPresenter with the ContentSource set to MiddleCell (your DP). Something like this:
<Style TargetType="{x:Type bridge:SeatCollection}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type bridge:SeatCollection}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<ContentPresenter ContentSource="MiddleCell" Grid.Row="1" Grid.Column="1" />
<!-- This is for the 'Hands' - Change as needed -->
<ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>