Problem with a DP PropertyChangedCallback not being invoked

Hi all,

I was wondering if someone could take a quick look at this sample. I
have a custom control, which has a single dependency property. When you
set this dependency property in XAML upon declaration of the control, I
need to set some properties on the child elements of this control
(specifically it's a child grid which has it's Visibility property
changed). I've set up a PropertyChangedCallback on this property to
make the change to the corresponding internal properties when the DP is
set. Here are the relevant snippets:


// the custom control class definition:

public partial class DataGrid : ItemsControl
{
// Dependency Properties
public static readonly DependencyProperty
ShowRowHeadersProperty = DependencyProperty.Register("ShowRowHeaders",
typeof(bool),
typeof(DataGrid),
new PropertyMetadata(
new
PropertyChangedCallback(ShowRowHeadersPropChanged)));


....

public static void ShowRowHeadersPropChanged(DependencyObject d,
DependencyPropertyChangedEventArgs e)
{
Console.WriteLine("In ShowRowHeadersPropChanged()");
bool value = (bool) e.NewValue;
((DataGrid) d).rowHeaderGrid.Visibility = value ?
Visibility.Visible : Visibility.Hidden;
}


and the XAML that creates the DataGrid in a window:
<ccataGrid Grid.Row="1" x:Name="OrderGrid" ShowRowHeaders="False" />


For some reason, the ShowRowHeadersPropChanged callback in never invoke
when I run this code. I've tried this exact same other pattern in
another example to test it and the callback does get invoked. Can any
MS folks have an idea on why the Callback might not be invoked?

Thanks, any help is appreciated!

Jason