. */ namespace Doctrine\Common; use Doctrine\Common\Events\Event; /** * The EventManager is the central point of Doctrine's event listener system. * Listeners are registered on the manager and events are dispatched through the * manager. * * @author Roman Borschel * @author Guilherme Blanco * @since 2.0 */ class EventManager { /** * Map of registered listeners. * => * * @var array */ private $_listeners = array(); /** * Dispatches an event to all registered listeners. * * @param string $eventName The name of the event to dispatch. The name of the event is * the name of the method that is invoked on listeners. * @param EventArgs $eventArgs The event arguments to pass to the event handlers/listeners. * If not supplied, the single empty EventArgs instance is used. * @return boolean */ public function dispatchEvent($eventName, EventArgs $eventArgs = null) { if (isset($this->_listeners[$eventName])) { $eventArgs = is_null($eventArgs) ? EventArgs::getEmptyInstance() : $eventArgs; foreach ($this->_listeners[$eventName] as $listener) { $listener->$eventName($eventArgs); } return ! $eventArgs->getDefaultPrevented(); } return true; } /** * Gets the listeners of a specific event or all listeners. * * @param string $event The name of the event. * @return */ public function getListeners($event = null) { return $event ? $this->_listeners[$event] : $this->_listeners; } /** * Checks whether an event has any registered listeners. * * @param string $event * @return boolean */ public function hasListeners($event) { return isset($this->_listeners[$event]); } /** * Adds an event listener that listens on the specified events. * * @param string|array $events The event(s) to listen on. * @param object $listener The listener object. */ public function addEventListener($events, $listener) { // TODO: maybe check for duplicate registrations? foreach ((array)$events as $event) { $this->_listeners[$event][] = $listener; } } /** * Adds an EventSubscriber. The subscriber is asked for all the events he is * interested in and added as a listener for these events. * * @param Doctrine\Common\EventSubscriber $subscriber The subscriber. */ public function addEventSubscriber(EventSubscriber $subscriber) { $this->addEventListener($subscriber->getSubscribedEvents(), $subscriber); } }