<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\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 <[email protected]>
* @author Jonathan Wage <[email protected]>
* @author Roman Borschel <[email protected]>
* @author Bernhard Schussek <[email protected]>
* @author Fabien Potencier <[email protected]>
* @author Jordi Boggiano <[email protected]>
* @author Jordan Alliot <[email protected]>
*/
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);
}
/**
* Gets the listener priority for a specific event.
*
* Returns null if the event or the listener does not exist.
*
* @param string $eventName The name of the event
* @param callable $listener The listener
*
* @return int|null The event listener priority
*/
public function getListenerPriority($eventName, $listener)
{
if (!isset($this->listeners[$eventName])) {
return;
}
foreach ($this->listeners[$eventName] as $priority => $listeners) {
if (false !== ($key = array_search($listener, $listeners, true))) {
return $priority;
}
}
}
/**
* {@inheritdoc}
*/
public function hasListeners($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)
{
krsort($this->listeners[$eventName]);
$this->sorted[$eventName] = call_user_func_array('array_merge', $this->listeners[$eventName]);
}
}