Sonata\Component\Order\OrderInterface::getDeliveryMethod PHP Method

    public function getDeliveryMethod();

 /**
  * Adds the delivery information from $order to $invoice
  *
  * @param InvoiceInterface $invoice
  * @param OrderInterface   $order
  */
 protected function addDelivery(InvoiceInterface $invoice, OrderInterface $order)
 {
     /** @var InvoiceElementInterface $invoiceElement */
     $invoiceElement = $this->invoiceElementManager->create();
     $invoiceElement->setQuantity(1);
     $invoiceElement->setPrice($order->getDeliveryCost());
     $invoiceElement->setUnitPriceExcl($order->getDeliveryCost());
     $invoiceElement->setUnitPriceInc($order->getDeliveryCost());
     $invoiceElement->setTotal($order->getDeliveryCost());
     $invoiceElement->setVatRate(0);
     $invoiceElement->setDesignation($this->deliveryPool->getMethod($order->getDeliveryMethod())->getName());
     $invoiceElement->setDescription($this->deliveryPool->getMethod($order->getDeliveryMethod())->getName());
     $invoiceElement->setInvoice($invoice);
     $invoice->addInvoiceElement($invoiceElement);
 }