_objectManager = $objectmanager; } /** * Create backend model by name * * @param string $modelName * @param array $arguments The object arguments * @return \Magento\Framework\App\Config\ValueInterface * @throws \InvalidArgumentException */ public function create($modelName, array $arguments = []) { $model = $this->_objectManager->create($modelName, $arguments); if (!$model instanceof \Magento\Framework\App\Config\ValueInterface) { throw new \InvalidArgumentException('Invalid config field backend model: ' . $modelName); } return $model; } }