Supplier/EventListener/SupplierDeliveryListener.php
public function onDelete(ResourceEventInterface $event)
    {
        $delivery = $this->getSupplierDeliveryFromEvent($event);

        if (null === $order = $delivery->getOrder()) {
            $changeSet = $this->persistenceHelper->getChangeSet($delivery);
            if (array_key_exists('order', $changeSet)) {
                $order = $changeSet['order'][0];
            }
        }
        if (null === $order) {
            throw new Exception\RuntimeException("Failed to retrieve supplier order.");
        }

        // Clear association
        $delivery->setOrder(null);

        // Trigger the supplier order update
        if (!$this->persistenceHelper->isScheduledForRemove($order)) {
            $this->scheduleSupplierOrderContentChangeEvent($order);
        }
    }
public function onDelete(ResourceEventInterface $event)
    {
        $delivery = $this->getSupplierDeliveryFromEvent($event);

        if (null === $order = $delivery->getOrder()) {
            $changeSet = $this->persistenceHelper->getChangeSet($delivery);
            if (array_key_exists('order', $changeSet)) {
                $order = $changeSet['order'][0];
            }
        }
        if (null === $order) {
            throw new Exception\RuntimeException("Failed to retrieve supplier order.");
        }

        // Clear association
        $delivery->setOrder(null);

        // Trigger the supplier order update
        if (!$this->persistenceHelper->isScheduledForRemove($order)) {
            $this->scheduleSupplierOrderContentChangeEvent($order);
        }
    }
Delete event handler.

@param ResourceEventInterface $event