[news.eclipse.modeling.gmf] Re: How to simulate a label of a link when l

[alessanderbotti@xxxxxxxxx (Alessander Botti Benevides)]

Hello Alex,

I tried to not upset you by asking for more specific instructions, but I 
spent most of these days trying to resolve it and could not make it work :(

I tried to follow your second sugestion, because I have added a derived 
attribute in EClass C (I'll call it "derivedCAttribute: String") which 
gets its value from an attribute of EClass B (I'll call it "BAttribute: 
String"), by an EReference "CtoB" from EClass C to EClass B. Also, there 
is an EReference "BtoC" which is the EOpposite of "CtoB". My tentative was:

(i) implement the method setDerivedCAttribute(String newCAttribute) in 
CImpl.java, making a call to eNotify:
setDerivedCAttribute(String newCAttribute) {
eNotify(new ENotificationImpl(this, Notification.SET, 
???Package.C__derivedCAttribute, "", ""));
}

(ii) modify setBAttribute(String newCAttribute) in BImpl.java in order to 
call my implementation of the method setDerivedCAttribute:
setBAttribute(String newCAttribute) {
..
this.getBtoC().setDerivedCAttribute("");
..
}

(iii) modify notifyChanged(Notification notification) in 
CItemProvider.java in order to fire a notification for derivedCAttribute:
public void notifyChanged(Notification notification) {
updateChildren(notification);

switch (notification.getFeatureID(C.class)) {
..
case ???Package.C__derivedCAttribute:
fireNotifyChanged(new ViewerNotification(notification, 
notification.getNotifier(), false, true));
return;
}
super.notifyChanged(notification);
}

(iv) implement handleNotificationEvent(Notification event) in 
CEditPart.java in order to properly change the label of the EClass C 
instance, when the associated EClass B instance has changed its BAttribute:
protected void handleNotificationEvent(Notification event) {
-code to update the label-
super.handleNotificationEvent(event);
}

So, I thought that when I change BAttribute, the setDerivedCAttribute 
would be called, making a notification and the method notifyChanged would 
send it to CEditPart.java, which would notice it by the method 
handleNotificationEvent and the label would be updated. But the problem is 
that the notification does not arrives on handleNotificationEvent. All the 
notifications which comes from proper EClass C attributes are working, and 
the other "normal" labels are fine. But, this scheme to indirectly notify 
instances of EClass C of changes on instances of EClass B is not 
working... could you help me more?

Thank you very much for your help!
Best regards,
Alessander