I'm on a roll today...

I have the following code delaring a dependency property inside a class called ActionScreen:

#region Dependency Properties & Methods

public string DescriptionHeader
{
    get { return (string)GetValue(DescriptionHeaderProperty); }
    set { SetValue(DescriptionHeaderProperty, value); }
}

// Using a DependencyProperty as the backing store for DescriptionHeader.  This enables animation, styling, binding, etc...
public static readonly DependencyProperty DescriptionHeaderProperty =
    DependencyProperty.Register("DescriptionHeader", typeof(string), typeof(ActionScreen), new UIPropertyMetadata("xxx"));

#endregion

I bind to this property in my Xaml as so:

                    <GridViewColumn DisplayMemberBinding="{Binding Description}" Header="{Binding DescriptionHeader}" Width="350" />

Now I want to be able to set the parameter from my code behind when I recieve an event - but it's not working:

public string DescColText { set { this.Dispatcher.Invoke(DispatcherPriority.Normal, new Action(delegate() { DescriptionHeader = value; })); } }