title: Same field multiple times Symfony 4 form
body: <p>I have an Entity <strong>Report</strong>, which is holds many <strong>Answers</strong>.</p>
  
  <pre><code>class Report
  {
      /**
       * @ORM\OneToMany(targetEntity="App\Entity\Answer", mappedBy="report")
       */
       private $answers; 
       ...
  }
  
  class Answer
  {
  
      /**
       * @ORM\ManyToOne(targetEntity="Report", inversedBy="answers")
       */
       private $report;
       ...
  }
  </code></pre>
  
  <p>I add the questions manually in my <strong>ReportType</strong> (I know this is not the best aproach but the questions will never change and I'm only interested in the answers.)</p>
  
  <pre><code>class ReportAnswersType extends AbstractType
  {
  
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
  
          $builder-&gt;add('answers', ChoiceType::class, array(
              'label' =&gt; 'Room state',
              'multiple' =&gt; false, 'expanded' =&gt; false,
              'choices'  =&gt; array('OK' =&gt; 'OK', 'NG' =&gt; 'NG', 'NP' =&gt; 'NP',),
          ))
          -&gt;add('answers', IntegerType::class, array(
              'label' =&gt; 'Temperature',
          ))
          -&gt;add('answers', ChoiceType::class, array(
              'label' =&gt; 'Is it good?',
              'multiple' =&gt; false, 'expanded' =&gt; false,
              'choices'  =&gt; array('YES' =&gt; 'YES', 'NO' =&gt; 'NO',),
          ))
          ...
      }
      -&gt;add('save', SubmitType::class);
  }
  
  public function configureOptions(OptionsResolver $resolver)
  {
      $resolver-&gt;setDefaults(array(
          'data_class' =&gt; Report::class,
      ));
  }
  </code></pre>
  
  <p>What I would like this to do is to generate a Form with 3 questions and insert each of the answers in the database.<br>
  But the rendered form only shows the last question (because with each <em>->add('answers', ...)</em> I replace the last one added).</p>
  
  <p>I tried different solutions to solve this:  </p>
  
  <ul>
  <li>Following the documentation on <a href="http://symfony.com/doc/current/form/form_collections.html" rel="nofollow noreferrer">How to Embed a Collection of Forms</a>, which, consists in adding each answer (with a label of the question) to the Report in the Controller and then rendering the ReportType. The problem about this is that each of my questions have different type (Choice, Text, Integer...) and I don't know how to customize them individually.</li>
  <li>And I also tried to do <a href="https://stackoverflow.com/questions/36202875/symfony3-createformbuilder-with-loop-of-add?noredirect=1&amp;lq=1">this</a> in my ReportType but it only shows the last question added.</li>
  </ul>
  
  <p>I appreciate any help, thanks!</p>