Symfony 2.6 - 按名称呈现个人选择字段（收音机，复选框）

Question

How can I render an individual field (single radio/checkbox input field) in Twig in Symfony 2.6?

Let's say I have a simple form:

class TransportType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
            $builder->add('transport', 'choice', array(
                'choices' => array(
                    'road' => 'Car/bus',
                    'train' => 'Train',
                ),
                'expanded' => true,
                'multiple' => false
            ));
    }

In previous Symfony2 versions I could just use:

{{ form_widget(form.transport.road) }}
{{ form_widget(form.transport.train) }}

to render individual radio buttons, but it doesn't seem to work anymore. I know I can use:

{{ form_widget(form.transport[0]) }}
{{ form_widget(form.transport[1]) }}

but it's less flexible. Of course I can iterate over the collection and check for name, but this seems like unnecessary hassle. Isn't there an easier way?

I tried offsetGet (which is supposed to return a child by name), but it also works only with array index.

Answer 1

It appears this is not possible with the latest versions of Symfony (i.e. >= 2.6). I recall in previous versions, when the form builder displayed the choices array, it was generating the choices like this:

<select>
    <option value="road">Car/Bus</option>
    <option value="train">Train</option>
</select>

This, however, has been changed in the recent versions to the following:

<select>
    <option value="0">Car/Bus</option>
    <option value="1">Train</option>
</select>

The selected option is then normalized and then you get the expected value you've set in the FormType class. You can read more about normalization here.

Also, If you write {{ debug(form.transport) }} in Symfony >= 2.6, you can see the form/field array and what you can use from it.