Register event handler for corresponding event.
Register event handler for corresponding event.
event class
corresponding event handler
the handler registration, can be stored in order to remove the handler later
Fire event to all registered handlers within the registry.
Fire event to all registered handlers within the registry.
event type
event to be fired
Dispatches EventObjects to interested parties.
Eases decoupling by allowing objects to interact without having direct dependencies upon one another, and without requiring event sources to deal with maintaining handler lists.