Observers are objects listening to EventDispatchers.
They are mostly used as bases for UIs in the context of the DC.
is a base class for observers.
Observers have methods listening to certain events. Use the listen decorator above to make the connections. The actual event subscriptions are done in the constructor.
The signature of the listeners always is:
listener(dispatcher, arg) -> ignored
dispatcher is the EventDispatcher instance propagating the event. It has lots of useful attributes explained in base.event’s notifyXXX docstrings.
You can listen to anything that has a notify method in the EventDispatcher.