5. Events

<?php
namespace metadigit\core\event;
interface EventDispatcherInterface {

	/**
	 * Add an Event listener on the specified event
	 * @param string   $eventName the name of the event to listen for
	 * @param callable $callback  the callback function to be invoked
	 * @param int      $priority  trigger precedence on the listeners chain (higher values execute earliest)
	 * @throws \Exception
	 */
	function listen($eventName, $callback, $priority=1);

	/**
	 * Trigger an Event, calling attached listeners
	 * @param string        $eventName  the name of the event
	 * @param mixed         $target     Event's target
	 * @param array         $params     Event's parameters
	 * @param Event|null    $Event      optional custom Event object
	 * @return Event the Event object
	 */
	function trigger($eventName, $target=null, array $params=null, $Event=null);
}

<events>
	<event name="dispatcher:controller">
		<listeners>
			<listener>myproject.apps.web.SessionManager->start</listener>
		</listeners>
	</event>
	<event name="dispatcher:view">
		<listeners>
			<listener>myproject.apps.web.SessionManager->end</listener>
		</listeners>
	</event>
</events>