code: protected function createController($controller)
      {
          $parts = explode(':', $controller);
          if (count($parts) === 2) {
              $service = $this->container->get($parts[0]);
  
              return array($service, $parts[1]);
          }
  
          $controller = parent::createController($controller);
          if ($controller[0] instanceof ContainerAwareInterface) {
              $controller[0]->setContainer($this->container);
          }
  
          return $controller;
      }
docs: Returns a callable for the given controller.
  
  @param string $controller A Controller string
  
  @return callable