AfterLineItemAddedEvent example

$alreadyExists = $cart->has($item->getId());
            $cart->add($item);

            $this->eventDispatcher->dispatch(new BeforeLineItemAddedEvent($item, $cart, $context, $alreadyExists));
        }

        $cart->markModified();

        $cart = $this->cartCalculator->calculate($cart, $context);
        $this->cartPersister->save($cart, $context);

        $this->eventDispatcher->dispatch(new AfterLineItemAddedEvent($items, $cart, $context));
        $this->eventDispatcher->dispatch(new CartChangedEvent($cart, $context));

        return new CartResponse($cart);
    }
}