Homec4science
Diffusion libphutil (stable) Browse

libphutil/src/events/engine/PhutilEventEngine.php
48149a97a273stable

Last Change
Raw File

PhutilEventEngine.php
View Options

<?php
/*
* Copyright 2012 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @group event
*/
class PhutilEventEngine {
private static $instance;
private $listeners = array();
private function __construct() {
// <empty>
}
public static function getInstance() {
if (!self::$instance) {
self::$instance = new PhutilEventEngine();
}
return self::$instance;
}
public function addListener(PhutilEventListener $listener, $type) {
$this->listeners[$type][] = $listener;
return $this;
}
/**
* Get all the objects currently listening to any event.
*/
public function getAllListeners() {
$listeners = array_mergev($this->listeners);
$listeners = mpull($listeners, null, 'getListenerID');
return $listeners;
}
public static function dispatchEvent(PhutilEvent $event) {
$instance = self::getInstance();
$listeners = idx($instance->listeners, $event->getType(), array());
$global_listeners = idx(
$instance->listeners,
PhutilEventType::TYPE_ALL,
array());
// Merge and deduplicate listeners (we want to send the event to each
// listener only once, even if it satisfies multiple criteria for the
// event).
$listeners = array_merge($listeners, $global_listeners);
$listeners = mpull($listeners, null, 'getListenerID');
foreach ($listeners as $listener) {
if ($event->isStopped()) {
// Do this first so if someone tries to dispatch a stopped event it
// doesn't go anywhere. Silly but less surprising.
break;
}
$listener->handleEvent($event);
}
}
}
c4science · Help