Updating Entity OneToMany relationship by passing arraycollection - php

Question

Im trying to change an old arraycolection of $linhas for a new one by using the method
setLinhas(Arraycollection $linhas)
but what happens when it does the changes is that internally he creates a new object with the new lines and dont update the old object with the new lines. It creates a new instance with the same values as the old object. It was suppose to update the same object and not create a new one!
Entity's Property :
/**
* #var ArrayCollection
*
* #ORM\OneToMany(targetEntity="AppBundle\Entity\LinhasPrecos", mappedBy="preco",orphanRemoval=true,cascade={"persist","merge"})
*/
protected $linhas;
/**
* #param $linhas
*/
public function setLinhas($linhas)
{
$this->linhas = new ArrayCollection($linhas);
}
In the service:
$oldObject->setLinhas($newObectWithNewLinhas->getLinhas());
$this->em->persist($oldObject);
but if I do the change manually it will work:
$oldLinhas = $oldObject->getLinhas()->getValues();
foreach($oldLinhas as $oldLinha)
{
$oldObject->removeLinha($oldLinha);
}
$linhaToCopy = $newObectWithNewLinhas->getLinhas()->getValues();
foreach($linhasCopyNew as $linhaCopyNew)
{
$oldObject->addLinha($linhaCopyNew);
}
thanks in advance!

Answer 1

You are doing it wrong!
use this constructor and setter instead:
Preco
use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;
/**
* #ORM\Entity
*/
class Preco
{
//...
/**
* #var Collection
*
* #ORM\OneToMany(targetEntity="AppBundle\Entity\LinhasPrecos", mappedBy="preco", orphanRemoval=true, cascade={"persist","merge"})
*/
protected $linhas;
//...
public function __construct()
{
$this->linhas = new ArrayCollection();
}
public function setLinhas($linhas)
{
$this->linhas = $linhas;
}
}
Notice
You should pass a doctrine collection into setLinhas.
This way you are totally replacing an old collection, with the new collection (and not adding an element to the old collection).