Render custom entity type field in form (Symfony) - forms

Question

I got stuck while trying to customize the rendering of a specific field in my form.
It looks like this:
$builder->add('players', 'entity', array(
'class' => 'Acme\Bundle\Entity\Player',
'expanded' => true,
'multiple' => true,
'required' => false,
));
The form itself is beeing rendered with a simple:
{% block form_content %}
{% form_theme form 'AcmeBundle:Form:fields_child.html.twig' %}
{{ form_widget(form) }}
{% endblock %}
Now inside fields_child.html.twig i'm extending from another form template but there is nothing special there.
My HTML looks like this:
Players:
- [checkbox-input] 1
Where 1 equals the id of the only player in the database. However instead of rendering the ID im trying to render his picture and full name after the checkbox.
I have tried many combinations of the form theming to override it but failed each time.
Could someone post the twig block to render what i want here?
Thanks

Answer 1

You have to create custom form field type together with custom widget template for it.
http://symfony.com/doc/current/cookbook/form/create_custom_field_type.html

Answer 2

I recently ran into this problem (was a little bit different situation. I needed to show products as table with checkboxes..), Form's child data always returned null value that's why I ended up with this (dirty:)) solution:
Controller action:
...
$productRepository = $entityManager->getRepository('VendorMyBundle:Product');
$products = [];
$formChildren = $productListForm->createView()->children;
foreach ($formChildren['products'] as $formProduct) {
$formProductId = $formProduct->vars['value'];
$productEntity = $productRepository->find($formProductId);
$products[$formProductId] = $productEntity;
}
...
return $this->render('TEMPLATE', [
'productListForm' => $productListForm->createView(),
'products' => $products,
]);
Template:
...
{% for productForm in productListForm.products %}
{% set id = productForm.vars.value %}
<tr>
<td class="check">
{{ form_widget(productForm) }}
</td>
<td class="photo">
{% if products[id].getImages().isEmpty() == false %}
{% set productImage = products[id].getImages().first() %}
<img src="{{ productImage.getWebPath() | imagine_filter('st_product_cabinet_thumbnail') }}" />
{% else %}
<span class="no-image">No image</span>
{% endif %}
</td>
<td class="title">
{{ products[id].getName() }}
</td>
<td class="status">
{{ products[id].getStatusName(products[id].getStatus()) }}
</td>
<td class="price">
<ul>
{% for productPrice in products[id].getPrices() %}
<li>{{ productPrice.getValue() ~ ' ' ~ productPrice.getCurrencyCode() }}</li>
{% endfor %}
</ul>
</td>
</tr>
{% endfor %}
...