/** * Disable fields depending on product type * * @return $this */ protected function _disableFields() { if ($this->getDisabled() || $this->_isProductComposite()) { $this->_qty->setDisabled('disabled'); } if (!$this->_isProductComposite() && $this->_qty->getValue() === null) { $this->setDisabled('disabled'); } if ($this->isLocked()) { $this->_qty->lock(); } return $this; }