title: Change label in submitted form - finishView function?
body: <p>How could i change the label of a form field after a submit of them?</p>
  
  <p>Example form</p>
  
  <pre><code>class TestType extends AbstractType
  {
      public function buildForm(FormBuilderInterface $builder, array $options)
      {
          $builder
              -&gt;add('test', 'number')
              -&gt;add($options['data']-&gt;getId() &gt; 0 ? 'save' : 'add', 'submit')
          ;
      }
  
      public function finishView(FormView $view, FormInterface $form, array $options)
      {
          if($form-&gt;has('add'))
          {
              $form-&gt;remove('add');
              $form-&gt;add('add', 'submit', array('label' =&gt; 'save'));
          }
      }
  
      public function getName()
      {
          return '';
      }
  }
  </code></pre>
  
  <p>The form is completely generated with "{{ form(form) }}".
  I only use the FormType.
  There is a add button if the data['id'] is lower as 1. if the id is higher as 0 there is a save button.</p>
  
  <p>After the first submit of a new form, the entity is saved and after finished page load i see the "add" field instead the "save" field.</p>
  
  <p>If i reload the complete page manually, i see the save button...</p>