Elgg\WidgetsService::registerType PHP Method

    public function registerType(WidgetDefinition $definition)
    {
        if (!$definition instanceof WidgetDefinition) {
            return false;
        }
        $id = $definition->id;
        if (!$id) {
            return false;
        }
        $this->widgets[$id] = $definition;
        return true;
    }