[news.eclipse.platform] Re: [Databinding] Problem with AggregateValidati

[Kai Schlamp <schlamp@xxxxxx>]

So, Schroedinger's cat ... nice analogy ... I hope my 
AggregateValidationStatus doesn't contain any transitional states ;-)

And yes, it works now when calling getValue inside the change listener.
Is there an easy way to get the AggregateValidationStatus from within 
the change listener? A "(AggregateValidationStatus) event.getSource())" 
results in a ClassCastException (java.lang.ClassCastException:
org.eclipse.core.databinding.AggregateValidationStatus$1 cannot be
cast to org.eclipse.core.databinding.AggregateValidationStatus).
Do I really have to pass the AggregateValidationStatus to the change 
listener myself?

Thank you,
Kai

> Are you doing anything with the value of the AggregateValidationStatus? 
> in the change listener?  AVS is backed by a ComputedValue which fires an 
> event once and doesn't fire any more until you look at the new value. 
> It's kind of like Schroedinger's cat--you don't get any more change 
> events until you look in the safe.  See 
> ObservableTracker.getterCalled(IObservable).  Then see IObservableValue 
> and look for methods tagged @TrackedGetter.
>
> We do this to avoid an event storm if several observables are changed 
> rapidly.  I think it will fix your problem just to call getValue() on 
> the AVS inside the change listener.