Many To One relationship not working in Symfony - symfony

Question

I have set the relationship on the entity's to set many customers to a user entity as a collection and added Multiple to the form field...it's posting ok it's just not updating the user_id in the customer table but it was when using OneToOne relation. Any help would be appreciated.
User entity code
/**
* #var Customer[]
* #ORM\OneToMany(targetEntity="App\Entity\Customer", mappedBy="user", cascade={"all"})
* #ORM\JoinColumn(nullable=true)
*/
private $customer;
public function __construct()
{
$this->staffUsers = new ArrayCollection();
$this->customer = new ArrayCollection();
}
/**
* #param Collection|null $customer
* #return $this
*/
public function setCustomer(?Collection $customer): self
{
$this->customer = $customer;
return $this;
}
Customer entity code
/**
* #ORM\ManyToOne(targetEntity="App\Entity\User", inversedBy="customer", cascade={"all"})
*/
private $user;
/**
* #return User|null
*/
public function getUser(): ?User
{
return $this->user;
}
/**
* #param User|null $user
* #return $this
*/
public function setUser(?User $user): self
{
$this->user = $user;
return $this;
}
Controller code
public function newUser(Request $request, UserPasswordEncoderInterface $encoder) : Response
{
/** #var UserRepository $userRepo */
$userRepo = $this->getDoctrine()->getRepository(User::class);
$customer = new Customer();
// make form
$form = $this->createForm(UserType::class,new User());
$form->handleRequest($request);
if($form->isSubmitted() && $form->isValid()){
/** #var User $newUser */
$newUser = $form->getData();
// dump($newUser);
// die();
// hold user roles
$roles = ['ROLE_USER'];
// check if admin role
$adminRole = (bool)$form->get('adminRole')->getData();
if($adminRole){
$roles[]='ROLE_ADMIN';
}
// is a customer selected?
if($newUser->getCustomer() && $newUser->getCustomer()->count() > 0){
$roles[]='ROLE_CUSTOMER';
}
$newUser->setRoles($roles);
// encode pw
$newUser->setPassword(
$encoder->encodePassword($newUser,$newUser->getPassword())
);
// create
$userRepo->insert($newUser);
return $this->redirectToRoute('usersListing');
}
return $this->render('admin/users/user-form.html.twig',[
'form'=>$form->createView()
]);
}
Customer entity type on User form
->add('customer',EntityType::class,[
'required'=>false,
'multiple' => true,
'attr'=>[
'class'=>'selectpicker form-control',
'multiple' =>'multiple',
'data-width' => "100%"
],
'label'=>'Customer(s)',
'placeholder'=>'N/A',
'class'=>Customer::class,
'query_builder'=>function (EntityRepository $er) {
return $er->createQueryBuilder('c')
->orderBy('c.lname', 'ASC')
->orderBy('c.fname','ASC');
},
'constraints'=>[
new Callback(function(?Collection $customers, ExecutionContextInterface $context) use($userRepo){
// check if the customer is already linked to a user
if($customers && $customers->count() > 0){
/** #var Customer $customer */
foreach($customers as $customer){
if($customer->getUser()){
$context->addViolation('Customer Is Already Linked To User: ' . $customer->getUser()->getUsername());
return false;
}
}
}
return true;
})
]
])

Answer 1

Rename property customer to customers and function from setCustomer to setCustomers, you should also create an addCustomer method in your User class:
public function addCustomer(Customer $customer)
{
$this->customers[] = $customer;
$customer->setUser($this); // sets the owning side, without this your will end up with user_id equal to null
}
And whenever you want to add a customer you just invoke the addCustomer method.
If you want to use the setCustomers method make sure you set the user in your customer entity.