public override void ElementRemoved(Microsoft.VisualStudio.Modeling.ElementRemovedEventArgs e)
 {
     if (e == null)
     {
         throw new ArgumentNullException("e");
     }
     CompartmentRuleHelper.HandleCompartmentUpdate(e.ModelElement as ElementLink, typeof(ViewPoint));
 }
        public override void RolePlayerChanged(RolePlayerChangedEventArgs e)
        {
            if (e == null)
            {
                throw new ArgumentNullException("e");
            }

            // we only need to update is the role player changed in the "parent" in the
            // embedding relationship.
            ViewPoint oldValue = e.OldRolePlayer as ViewPoint;
            ViewPoint newValue = e.NewRolePlayer as ViewPoint;

            CompartmentRuleHelper.HandleRolePlayerChangedRule(e.ElementLink,
                                                              oldValue, newValue);
        }