Omnipay\WechatPay\Message\CreateOrderRequest::getTradeType PHP Method

    public function getTradeType()
    {
        return $this->getParameter('trade_type');
    }

 public function getCodeUrl()
 {
     if ($this->isSuccessful() && $this->request->getTradeType() == 'NATIVE') {
         return $this->getData()['code_url'];
     } else {
         return null;
     }
 }