public function setLanguageService(LanguageService $languageService = null)
    {
        $this->languageService = $languageService instanceof LanguageService ? $languageService : GeneralUtility::makeInstance(LanguageService::class);
        if ($this->getBackendUser()) {
            $this->languageService->init($this->getBackendUser()->uc['lang']);
        }
    }