public function getUniqueIdentifier()
    {
        $formDefinition = $this->getRootForm();
        $uniqueIdentifier = sprintf('%s-%s', $formDefinition->getIdentifier(), $this->identifier);
        $uniqueIdentifier = preg_replace('/[^a-zA-Z0-9-_]/', '_', $uniqueIdentifier);
        return lcfirst($uniqueIdentifier);
    }