/**
* Get EventDispatcher instance.
*
* @param EventDispatcherInterface $dispatcher
*
* @return EventDispatcherInterface
*/
public static function getManager(EventDispatcherInterface $dispatcher = null)
{
if (self::$dispatcher) {
return self::$dispatcher;
}
if (null === $dispatcher) {
throw new \InvalidArgumentException('No event dispatcher was specified or previously loaded');
}
self::$dispatcher = $dispatcher;
return self::$dispatcher;
}
