[news.eclipse.modeling.gmf] How can I add Items to a compartment dynamic

[Ralph <ralph.schreder@xxxxxx>]

Hi,
when my special ListCompartment is created, I want to add items to it. I 
tried it in the method createFigure by

MyNodeCompartmentEditPart.java:

	public IFigure createFigure() {
		ResizableCompartmentFigure result = (ResizableCompartmentFigure) 
super.createFigure();
		result.setTitleVisibility(false);


		BusinessAttribute model = IsfFactory.eINSTANCE.createBusinessAttribute();
		NodeImpl node = (NodeImpl)this.getModel();
		EObject elem = node.getElement();
		BusinessEntity p = (BusinessEntity)elem;
		p.getAttributeList().add(model);
		EditPart subEditPart = 
getViewer().getEditPartFactory().createEditPart(this, model);
		this.addChildVisual(subEditPart, this.getChildren().size());


		return result;
	}

I receive an exception.
Has anybody an idea?

Thanks,
Ralph