Symfony Iterating over ArrayCollection - symfony

Question

In my app I have 2 entities; User & Booking.
Booking entity:
namespace App\Entity;
/**
* #ORM\Table(name="booking")
* #ORM\Entity(repositoryClass="App\Repository\BookingRepository")
*/
class Booking
{
/**
* #ORM\Column(type="boolean")
* #Assert\NotBlank()
*/
private $isActive;
/**
* #ORM\ManyToOne(targetEntity="App\Entity\User", inversedBy="bookings")
*/
private $user;
User entity:
/**
* #ORM\Table(name="app_user")
* #ORM\Entity(repositoryClass="App\Repository\UserRepository")
* #UniqueEntity(fields="email", message="This email address is already in use")
*/
class User implements AdvancedUserInterface
{
/**
* #ORM\Column(type="string", length=255, unique=true)
* #Assert\NotBlank()
* #Assert\Email()
*/
private $email;
/**
* #ORM\OneToMany(targetEntity="App\Entity\Booking", mappedBy="user")
* #Expose
*/
private $bookings;
/**
* User constructor.
*/
public function __construct()
{
$this->bookings = new ArrayCollection();
}
I tried to add a function to my user entity that returns the active booking, I tried this:
/**
* #return mixed
*/
public function getActiveBooking()
{
foreach( $this->bookings as $booking ) {
if( $booking->getIsActive() ) {
return $booking;
}
}
}
But I get the following error: Error: Call to a member function getRoom() on null
When I call it using $user->getActiveBooking()->getRoom()->getId()

Answer 1

Make sure that the user you are working with has an active booking.
getActiveBooking() is returning null because it seems user does not have an active booking.
That's why you are getting an error that you cannot call getRoom() on null because the previous function has returned null.

Answer 2

Have you tried to add a joinColumn like this:
/**
* #ORM\ManyToOne(targetEntity="App\Entity\User", inversedBy="bookings")
* #ORM\JoinColumn(name="user_id", referencedColumnName="id", nullable=false)
*/
private $user;