4 * This file is part of the Symfony package.
6 * (c) Fabien Potencier <fabien@symfony.com>
8 * For the full copyright and license information, please view the LICENSE
9 * file that was distributed with this source code.
12 namespace Symfony\Component\EventDispatcher;
15 * The EventDispatcherInterface is the central point of Symfony's event listener system.
17 * Listeners are registered on the manager and events are dispatched through the
20 * @author Guilherme Blanco <guilhermeblanco@hotmail.com>
21 * @author Jonathan Wage <jonwage@gmail.com>
22 * @author Roman Borschel <roman@code-factory.org>
23 * @author Bernhard Schussek <bschussek@gmail.com>
24 * @author Fabien Potencier <fabien@symfony.com>
25 * @author Jordi Boggiano <j.boggiano@seld.be>
26 * @author Jordan Alliot <jordan.alliot@gmail.com>
28 class EventDispatcher implements EventDispatcherInterface
30 private $listeners = array();
31 private $sorted = array();
36 public function dispatch($eventName, Event $event = null)
38 if (null === $event) {
42 $event->setDispatcher($this);
43 $event->setName($eventName);
45 if ($listeners = $this->getListeners($eventName)) {
46 $this->doDispatch($listeners, $eventName, $event);
55 public function getListeners($eventName = null)
57 if (null !== $eventName) {
58 if (!isset($this->listeners[$eventName])) {
62 if (!isset($this->sorted[$eventName])) {
63 $this->sortListeners($eventName);
66 return $this->sorted[$eventName];
69 foreach ($this->listeners as $eventName => $eventListeners) {
70 if (!isset($this->sorted[$eventName])) {
71 $this->sortListeners($eventName);
75 return array_filter($this->sorted);
79 * Gets the listener priority for a specific event.
81 * Returns null if the event or the listener does not exist.
83 * @param string $eventName The name of the event
84 * @param callable $listener The listener
86 * @return int|null The event listener priority
88 public function getListenerPriority($eventName, $listener)
90 if (!isset($this->listeners[$eventName])) {
94 foreach ($this->listeners[$eventName] as $priority => $listeners) {
95 if (false !== in_array($listener, $listeners, true)) {
104 public function hasListeners($eventName = null)
106 return (bool) $this->getListeners($eventName);
112 public function addListener($eventName, $listener, $priority = 0)
114 $this->listeners[$eventName][$priority][] = $listener;
115 unset($this->sorted[$eventName]);
121 public function removeListener($eventName, $listener)
123 if (!isset($this->listeners[$eventName])) {
127 foreach ($this->listeners[$eventName] as $priority => $listeners) {
128 if (false !== ($key = array_search($listener, $listeners, true))) {
129 unset($this->listeners[$eventName][$priority][$key], $this->sorted[$eventName]);
137 public function addSubscriber(EventSubscriberInterface $subscriber)
139 foreach ($subscriber->getSubscribedEvents() as $eventName => $params) {
140 if (is_string($params)) {
141 $this->addListener($eventName, array($subscriber, $params));
142 } elseif (is_string($params[0])) {
143 $this->addListener($eventName, array($subscriber, $params[0]), isset($params[1]) ? $params[1] : 0);
145 foreach ($params as $listener) {
146 $this->addListener($eventName, array($subscriber, $listener[0]), isset($listener[1]) ? $listener[1] : 0);
155 public function removeSubscriber(EventSubscriberInterface $subscriber)
157 foreach ($subscriber->getSubscribedEvents() as $eventName => $params) {
158 if (is_array($params) && is_array($params[0])) {
159 foreach ($params as $listener) {
160 $this->removeListener($eventName, array($subscriber, $listener[0]));
163 $this->removeListener($eventName, array($subscriber, is_string($params) ? $params : $params[0]));
169 * Triggers the listeners of an event.
171 * This method can be overridden to add functionality that is executed
174 * @param callable[] $listeners The event listeners
175 * @param string $eventName The name of the event to dispatch
176 * @param Event $event The event object to pass to the event handlers/listeners
178 protected function doDispatch($listeners, $eventName, Event $event)
180 foreach ($listeners as $listener) {
181 if ($event->isPropagationStopped()) {
184 call_user_func($listener, $event, $eventName, $this);
189 * Sorts the internal list of listeners for the given event by priority.
191 * @param string $eventName The name of the event
193 private function sortListeners($eventName)
195 krsort($this->listeners[$eventName]);
196 $this->sorted[$eventName] = call_user_func_array('array_merge', $this->listeners[$eventName]);