protected override void Invoke(object parameter)
{
Assembly libraryAssembly = null;
UserControl hostControl = this.AssociatedObject.GetSelfAndAncestors().OfType <UserControl>().FirstOrDefault();
if (hostControl != null)
{
libraryAssembly = hostControl.GetType().Assembly;
}
InteractionContext.GoToScreen(TargetScreen, libraryAssembly);
}