[news.eclipse.modeling.gmf] Custom layout at diagram creation

[Esteban DUGUEPEROUX <dugueperoux.esteban@xxxxxxx>]

Hi,

I wish to layout my nodes in a TopDown Layout, I create a diagram with 
default model elements in createInitialModel() method and create 
equivalent nodes with ViewService.createDiagram() and 
ViewService.createNode(),
Then I initialize bounds of my nodes using the following code :

Iterator entityNodeIterator = diagram.getChildren().iterator();;
int xMargin = 10;
int yMargin = 10;
int yCurrent = yMargin;
while(entityNodeIterator.hasNext()){
	Node entityNode = (Node) entityNodeIterator.next();
	Bounds bounds = (Bounds) entityNode.getLayoutConstraint();
	bounds.setX(xMargin);
	bounds.setY(yCurrent);
	yCurrent += bounds.getHeight()+yMargin;
	entityNode.setLayoutConstraint(bounds);
}

but my problem is that bounds.getHeight() == -1,

How can I initialize my node size to correct value depending of their 
content?

Thanks.