vendor/symfony/event-dispatcher/Symfony/Component/EventDispatcher/EventDispatcherInterface.php

   1 <?php
   2
   3 /*
   4  * This file is part of the Symfony package.
   5  *
   6  * (c) Fabien Potencier <fabien@symfony.com>
   7  *
   8  * For the full copyright and license information, please view the LICENSE
   9  * file that was distributed with this source code.
  10  */
  11
  12 namespace Symfony\Component\EventDispatcher;
  13
  14 /**
  15  * The EventDispatcherInterface is the central point of Symfony's event listener system.
  16  * Listeners are registered on the manager and events are dispatched through the
  17  * manager.
  18  *
  19  * @author Bernhard Schussek <bschussek@gmail.com>
  20  *
  21  * @api
  22  */
  23 interface EventDispatcherInterface
  24 {
  25     /**
  26      * Dispatches an event to all registered listeners.
  27      *
  28      * @param string $eventName The name of the event to dispatch. The name of
  29      *                          the event is the name of the method that is
  30      *                          invoked on listeners.
  31      * @param Event $event The event to pass to the event handlers/listeners.
  32      *                          If not supplied, an empty Event instance is created.
  33      *
  34      * @return Event
  35      *
  36      * @api
  37      */
  38     public function dispatch($eventName, Event $event = null);
  39
  40     /**
  41      * Adds an event listener that listens on the specified events.
  42      *
  43      * @param string   $eventName The event to listen on
  44      * @param callable $listener  The listener
  45      * @param integer  $priority  The higher this value, the earlier an event
  46      *                            listener will be triggered in the chain (defaults to 0)
  47      *
  48      * @api
  49      */
  50     public function addListener($eventName, $listener, $priority = 0);
  51
  52     /**
  53      * Adds an event subscriber.
  54      *
  55      * The subscriber is asked for all the events he is
  56      * interested in and added as a listener for these events.
  57      *
  58      * @param EventSubscriberInterface $subscriber The subscriber.
  59      *
  60      * @api
  61      */
  62     public function addSubscriber(EventSubscriberInterface $subscriber);
  63
  64     /**
  65      * Removes an event listener from the specified events.
  66      *
  67      * @param string|array $eventName The event(s) to remove a listener from
  68      * @param callable     $listener  The listener to remove
  69      */
  70     public function removeListener($eventName, $listener);
  71
  72     /**
  73      * Removes an event subscriber.
  74      *
  75      * @param EventSubscriberInterface $subscriber The subscriber
  76      */
  77     public function removeSubscriber(EventSubscriberInterface $subscriber);
  78
  79     /**
  80      * Gets the listeners of a specific event or all listeners.
  81      *
  82      * @param string $eventName The name of the event
  83      *
  84      * @return array The event listeners for the specified event, or all event listeners by event name
  85      */
  86     public function getListeners($eventName = null);
  87
  88     /**
  89      * Checks whether an event has any registered listeners.
  90      *
  91      * @param string $eventName The name of the event
  92      *
  93      * @return Boolean true if the specified event has any listeners, false otherwise
  94      */
  95     public function hasListeners($eventName = null);
  96 }