1. 8.5.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  2. 8.0.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  3. 8.1.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  4. 8.2.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  5. 8.3.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  6. 8.4.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher
  7. 8.6.x vendor/symfony/event-dispatcher/EventDispatcher.php EventDispatcher

The EventDispatcherInterface is the central point of Symfony's event listener system.

Listeners are registered on the manager and events are dispatched through the manager.

@author Guilherme Blanco <guilhermeblanco@hotmail.com> @author Jonathan Wage <jonwage@gmail.com> @author Roman Borschel <roman@code-factory.org> @author Bernhard Schussek <bschussek@gmail.com> @author Fabien Potencier <fabien@symfony.com> @author Jordi Boggiano <j.boggiano@seld.be> @author Jordan Alliot <jordan.alliot@gmail.com>

Hierarchy

Expanded class hierarchy of EventDispatcher

1 file declares its use of EventDispatcher

File

vendor/symfony/event-dispatcher/EventDispatcher.php, line 28

Namespace

Symfony\Component\EventDispatcher
View source
class EventDispatcher implements EventDispatcherInterface {
  private $listeners = array();
  private $sorted = array();

  /**
   * {@inheritdoc}
   */
  public function dispatch($eventName, Event $event = null) {
    if (null === $event) {
      $event = new Event();
    }
    $event
      ->setDispatcher($this);
    $event
      ->setName($eventName);
    if ($listeners = $this
      ->getListeners($eventName)) {
      $this
        ->doDispatch($listeners, $eventName, $event);
    }
    return $event;
  }

  /**
   * {@inheritdoc}
   */
  public function getListeners($eventName = null) {
    if (null !== $eventName) {
      if (!isset($this->listeners[$eventName])) {
        return array();
      }
      if (!isset($this->sorted[$eventName])) {
        $this
          ->sortListeners($eventName);
      }
      return $this->sorted[$eventName];
    }
    foreach ($this->listeners as $eventName => $eventListeners) {
      if (!isset($this->sorted[$eventName])) {
        $this
          ->sortListeners($eventName);
      }
    }
    return array_filter($this->sorted);
  }

  /**
   * {@inheritdoc}
   */
  public function hasListeners($eventName = null) {
    return (bool) count($this
      ->getListeners($eventName));
  }

  /**
   * {@inheritdoc}
   */
  public function addListener($eventName, $listener, $priority = 0) {
    $this->listeners[$eventName][$priority][] = $listener;
    unset($this->sorted[$eventName]);
  }

  /**
   * {@inheritdoc}
   */
  public function removeListener($eventName, $listener) {
    if (!isset($this->listeners[$eventName])) {
      return;
    }
    foreach ($this->listeners[$eventName] as $priority => $listeners) {
      if (false !== ($key = array_search($listener, $listeners, true))) {
        unset($this->listeners[$eventName][$priority][$key], $this->sorted[$eventName]);
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public function addSubscriber(EventSubscriberInterface $subscriber) {
    foreach ($subscriber
      ->getSubscribedEvents() as $eventName => $params) {
      if (is_string($params)) {
        $this
          ->addListener($eventName, array(
          $subscriber,
          $params,
        ));
      }
      elseif (is_string($params[0])) {
        $this
          ->addListener($eventName, array(
          $subscriber,
          $params[0],
        ), isset($params[1]) ? $params[1] : 0);
      }
      else {
        foreach ($params as $listener) {
          $this
            ->addListener($eventName, array(
            $subscriber,
            $listener[0],
          ), isset($listener[1]) ? $listener[1] : 0);
        }
      }
    }
  }

  /**
   * {@inheritdoc}
   */
  public function removeSubscriber(EventSubscriberInterface $subscriber) {
    foreach ($subscriber
      ->getSubscribedEvents() as $eventName => $params) {
      if (is_array($params) && is_array($params[0])) {
        foreach ($params as $listener) {
          $this
            ->removeListener($eventName, array(
            $subscriber,
            $listener[0],
          ));
        }
      }
      else {
        $this
          ->removeListener($eventName, array(
          $subscriber,
          is_string($params) ? $params : $params[0],
        ));
      }
    }
  }

  /**
   * Triggers the listeners of an event.
   *
   * This method can be overridden to add functionality that is executed
   * for each listener.
   *
   * @param callable[] $listeners The event listeners.
   * @param string     $eventName The name of the event to dispatch.
   * @param Event      $event     The event object to pass to the event handlers/listeners.
   */
  protected function doDispatch($listeners, $eventName, Event $event) {
    foreach ($listeners as $listener) {
      call_user_func($listener, $event, $eventName, $this);
      if ($event
        ->isPropagationStopped()) {
        break;
      }
    }
  }

  /**
   * Sorts the internal list of listeners for the given event by priority.
   *
   * @param string $eventName The name of the event.
   */
  private function sortListeners($eventName) {
    $this->sorted[$eventName] = array();
    krsort($this->listeners[$eventName]);
    $this->sorted[$eventName] = call_user_func_array('array_merge', $this->listeners[$eventName]);
  }

}

Members

Contains filters are case sensitive
Namesort descending Modifiers Type Description Overrides
EventDispatcher::$listeners private property
EventDispatcher::$sorted private property
EventDispatcher::addListener public function Adds an event listener that listens on the specified events. Overrides EventDispatcherInterface::addListener
EventDispatcher::addSubscriber public function Adds an event subscriber. Overrides EventDispatcherInterface::addSubscriber
EventDispatcher::dispatch public function Dispatches an event to all registered listeners. Overrides EventDispatcherInterface::dispatch
EventDispatcher::doDispatch protected function Triggers the listeners of an event.
EventDispatcher::getListeners public function Gets the listeners of a specific event or all listeners sorted by descending priority. Overrides EventDispatcherInterface::getListeners
EventDispatcher::hasListeners public function Checks whether an event has any registered listeners. Overrides EventDispatcherInterface::hasListeners
EventDispatcher::removeListener public function Removes an event listener from the specified events. Overrides EventDispatcherInterface::removeListener
EventDispatcher::removeSubscriber public function Removes an event subscriber. Overrides EventDispatcherInterface::removeSubscriber
EventDispatcher::sortListeners private function Sorts the internal list of listeners for the given event by priority.