/ comp / gb / observer
Observer (gb)
This class allows to catch the events raised by an object before its main event observer gets them.

The observer object will raise the same events as the observed object, and so you will handle them with the same handlers.

If you cancel an event in the observer event handler, the main event observer of the observed object will never see it.

See the TableView control source code for an example: it is implemented by using this method.

Symbols
This class is creatable.