function ContainerAwareEventDispatcher::getListenerPriority

File

core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php, line 165

Class

ContainerAwareEventDispatcher

A performance optimized container aware event dispatcher.

Namespace

Code

public function getListenerPriority($event_name, $listener) : ?int {
    if (!isset($this->listeners[$event_name])) {
        return NULL;
    }
    if (is_array($listener) && isset($listener[0]) && $listener[0] instanceof \Closure) {
        $listener[0] = $listener[0]();
    }
    // Resolve service definitions if the listener has not been found so far.
    foreach ($this->listeners[$event_name] as $priority => &$definitions) {
        foreach ($definitions as &$definition) {
            if (!isset($definition['callable'])) {
                // Once the callable is retrieved we keep it for subsequent method
                // invocations on this class.
                $definition['callable'] = [
                    $this->container
                        ->get($definition['service'][0]),
                    $definition['service'][1],
                ];
            }
            if (is_array($definition['callable']) && isset($definition['callable'][0]) && $definition['callable'][0] instanceof \Closure) {
                $definition['callable'][0] = $definition['callable'][0]();
            }
            if ($definition['callable'] === $listener) {
                return $priority;
            }
        }
    }
    return NULL;
}