How to pass another entity info into form in Symfony2? - symfony

Question

What is best practice to include another info in form from another entity?
I have Student Entity, Group Entity, StudentsGroup and Attendance Entity.
Student have id, code, and name.
Group have id and name.
StudentsGroup have id, group_id, and student_id.
Attendance have id, students_group_id, date and status.
Group can have many Student which saved in StudentsGroup. Why I make StudentsGroup? Because actually 1 Group can have some sub groups like SubjectsGroup etc. And Attendance save student information by StudentsGroup Id which same student can have different students_group_id.
Now, the problem is : How to show Student information in collection form of attendance?
All Entity relationship is declared as object, so actually we can access em freely from any entity. But I don't know how to do that in form. Here my form :
<?php
/* Collection Form */
$tanggal = new \DateTime($request->request->get('sifo_adminbundle_studentsgrouping')['tanggal']);
$attendances = new StudentsGrouping();
foreach ($entities as $temp) {
$entity = new Attendance();
$entity = $em->getRepository('SifoAdminBundle:Attendance')->findOneBy(array('studentsGrouping' => $temp, 'date' => $tanggal));
if ($entity){
$attendances->getAttendances()->add($entity);
}
}
$form = $this->createCollectionForm($attendances, $id, $tanggal);
return $this->render('SifoAdminBundle:DftAbsensi:manage.html.twig', array(
'form' => $form->createView(),
));
This is how I render it in twig :
{{ form_start(form_collection) }}
{{ form_row(form_collection.tanggal) }}
{% for attendance in form_collection.attendances %}
{{ form_row(attendance.status) }}
{% endfor %}
{{ form_end(form_collection) }}
## Concept ##
I'm thinking about creating entity and pass it into form like this :
foreach ($entities as $temp) {
$entity = new Student();
$entity = $em->getRepository('SifoAdminBundle:Student')->find($temp->getId());
if ($entity){
$entities[i] = $entity;
}
$i++
}
and then in twig show it like this :
{{ form_start(form_collection) }}
{{ form_row(form_collection.tanggal) }}
{% for key, attendance in form_collection.attendances %}
{{ entities[key].code }}
{{ entities[key].name }}
{{ form_row(attendance.status) }}
{% endfor %}
{{ form_end(form_collection) }}
But I feel not comfort with this. Am I really need to make new entity just for showing name and code from Student Entity? Is there a best practice to do this?

Answer 1

You can use entity field.
$builder->add('users', 'entity', array(
'class' => 'AcmeHelloBundle:User',
'multiple' => true, /* you can choose more than one */
'mapped' => false, /* if you are using the form with an entity */
'query_builder' => function(EntityRepository $er) {
/* use query builder to get correct results */
return $er->createQueryBuilder('u')->orderBy('u.username', 'ASC');
},
));
There are two important keys in above.
'multiple' => true ----- you can able to choose more than one
'mapped' => false ----- if you are using form with an entity, your form will automatically looks for a connection between these entities and if can not found, throws exception. to avoid of that problem you should set this option to false
http://symfony.com/doc/current/reference/forms/types/entity.html