When a viewStack changes, components aren't explicitly added or removed. They are just hidden and displayed.
You can do stuff using the show and hide event:
With a ViewStack you can also use the change event:
Depending on your specific needs, some of these may be better suited which relate to components being added or removed from the stage:
Exactly what i was looking for...
Tried those events a couple of weeks ago and didn't get any reactions... dont know why !