public function processFieldsChangeType(ContentTypeInterface $contentType, $fieldTypes)
    {
        foreach ($contentType->getFields() as $field) {
            if (!isset($fieldTypes[$field->getId()])) {
                continue;
            }
            if ($fieldTypes[$field->getId()] == $field->getType()) {
                continue;
            }

            $this->om->remove($field);

            $fieldClass = $this->configurationManager->getEntityClass('field');
            $newField = new $fieldClass;
            $newField->setType($field->getType());
            $newField->setContentType($field->getContentType());
            $newField->setName($field->getName());
            $newField->setSlug($field->getSlug());
            $newField->setRequired($field->isRequired());
            $newField->setSortOrder($field->getSortOrder());
            $newField->setOptions($field->getOptions());
            $newField->setHint($field->getHint());
            $this->om->persist($newField);
        }
    }