class ViewsSlideshowWidgetPluginManager

class ViewsSlideshowWidgetPluginManager extends DefaultPluginManager {
    
    /**
     * Constructs a new ViewsSlideshowWidgetPluginManager.
     *
     * @param \Traversable $namespaces
     *   An object that implements \Traversable which contains the root paths
     *   keyed by the corresponding namespace to look for plugin implementations.
     * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
     *   Cache backend instance to use.
     * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
     *   The module handler.
     */
    public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler) {
        parent::__construct('Plugin/ViewsSlideshowWidget', $namespaces, $module_handler, 'Drupal\\views_slideshow\\ViewsSlideshowWidgetInterface', 'Drupal\\views_slideshow\\Annotation\\ViewsSlideshowWidget');
        $this->alterInfo('views_slideshow_widget_info');
        $this->setCacheBackend($cache_backend, 'views_slideshow_widget');
    }
    
    /**
     * Gets the definition of all or filtered plugins for this type.
     *
     * @param mixed $type
     *   A string or an array of types to filter on.
     *
     * @return mixed
     *   An array of plugin definitions. Keys are plugin IDs.
     */
    public function getDefinitions($type = NULL) {
        $definitions = parent::getDefinitions();
        // Filter widgets to keep only required types.
        if (!empty($type)) {
            foreach ($definitions as $widgetId => $widgetInfo) {
                if (is_array($type) && !in_array($widgetInfo['type'], $type) || is_string($type) && $widgetInfo['type'] !== $type) {
                    unset($definitions[$widgetId]);
                }
            }
        }
        return $definitions;
    }

}