Impossible to access an attribute (“nom”) on a null variable

Question

I would like for each of my children, their picture appears but I have this error message that appears :

Impossible to access an attribute ("nom") on a null variable.

In my twig:

{% for eleve in eleves %}
  <div><img src="{{ asset('img/')~eleve.image.nom}}" alt="" width="200" height="200"></div> 
  <div>{{eleve.prenom}}</div>                             
{% endfor %}

In my controller :

/**
 * @Route("/accueilPrincipal", name="accueilPrincipal")
*/
public function eleve(Request $request, EntityManagerInterface $manager)
{
    // On récupere tous les eleves
    $repo = $this->getDoctrine()->getRepository(Image::class);
    $repo2 = $this->getDoctrine()->getRepository(Eleve::class);
    $images = $repo->findAll();
    $test = $repo2->findAll();

    $sexe = $this->getUser()->getSexe();
    $eleves = $this->getUser()->getElevestuteur1();
    $eleves2 = $this->getUser()->getElevestuteur2();

    $user = $this->getUser()->getNom();

    return $this->render('profile/accueilPrincipal.html.twig', [
        'eleves' => $eleves,
        'eleves2' => $eleves2,
        'user' => $user,
        'sexe' => $sexe,
        'images' => $images,
        'test' => $test,
    ]);
}

Answer 1

Examine the $eleves variable, and it should be a lot clearer. dump($eleves);die; before the return $this->render(...) will show you what is actually there, instead of what you think must be there, but you don't quite know.