symfony2 twig form theme for different subsites - forms

Question

I've got a symfony2 application with multiple styles. All 3 have their own html + css for rendering.
Something like "frontsite", "user dashboard" and "admin backend".
Now there is a difference in form theme to be used in all 3 subsites, so there is a (slightly) different theme for all of them.
Because of this I can set the theme in the symfony configuration, but for 2 of the 3 subsites it will be wrong.
I can set a theme manually using:
{% form_theme form 'MyUberCoolBundle:Form:theme.html.twig' %}
But I don't really want to do that for every form.
I could set that in a base-template, but then my form would always need to be called "form".
Is there a way to set the theme to be used in a base template so it will be used for all forms?

Answer 1

I was looking for something like that. Something to use a theme for FrontOffice and another one to use in the back office.
I got it. I use a normal configuration in the config.yml as normal for the FrontOffice like that:
twig:
globals:
frontend_form_theme: 'form/fields.html.twig'
And then I use in the main BackOffice themplate like layout.html.twig:
{% if oForm is defined %} {% form_theme oForm 'bootstrap_3_layout.html.twig' %} {% endif %}
So, bootstrap defined for all the forms with the name oForm.

Answer 2

So the other answers here work great when your pages only have one form and it's always named something constant, like form. In my scenario, however, I often have multiple forms with different names, so that approach doesn't work. Instead, what I did was create a custom twig function that applies the desired form theme to all forms passed into to the view:
Inside your WhateverTwigExtension.php: (see here for info on writing twig extensions)
class WhateverTwigExtension extends AbstractExtension
{
private $formRenderer;
public function __construct(FormRendererInterface $formRenderer)
{
$this->formRenderer = $formRenderer;
}
public function getFunctions()
{
return [
new TwigFunction('applyFormThemes', [$this, 'applyFormThemes']),
];
}
public function applyFormThemes(array $context, $themes)
{
foreach ($context as $variable) {
if ($variable instanceof FormView) {
$this->formRenderer->setTheme($variable, $themes);
}
}
}
}
Note that for symfony's autowiring to be able to inject the renderer into this extension, you'll have to alias it, so put something like this in your services.yml:
services:
Symfony\Component\Form\FormRendererInterface: '#twig.form.renderer'
Finally, in the base twig for your subsite, simply add:
{{ applyFormThemes(_context, 'my_form_theme.html.twig') }}
Also works for multiple themes:
{{ applyFormThemes(_context, ['my_form_theme.html.twig', 'other_form_theme.html.twig']) }}
And now all forms passed to that view will have your theme applied!
You can also still use the normal form_theme tag to override specific forms, as long as it comes after the applyFormThemes

Answer 3

to set a theme global for your application you can set it in the config
twig:
form_themes:
# Default:
- form_div_layout.html.twig
# Bootstrap:
- bootstrap_3_layout.html.twig
- bootstrap_3_horizontal_layout.html.twig
# Example:
- MyBundle::form.html.twig
See the full Twig config reference here

Answer 4

After looking around for an answer I came to the conclusion it is not possible to do this only in configuration.
We resorted to the following solution
in config.yml we configured a global twig variable:
twig:
globals:
frontend_form_theme: 'MyUberCoolBundle:Form:theme.html.twig'
Then we set the correct theme on the form itself just prior to rendering using the global variable.
This even allows us to use something different when desired.
{% form_theme form frontend_form_theme %}
{{ form_start(form) }}

Answer 5

This is possible, and works well. It assumes you are consistent with naming your root forms however.
First, setup a default form theme like described in the standard docs.
# twig.yaml
twig:
form_themes: ['form.html.twig'] # Default theme and front-end
Override the form theme for the primary form in your admin layout template.
# admin/layout.html.twig
{% if form is defined %}
{% form_theme form "admin/_form.html.twig" %}
{% endif %}
{% block content %}{% endblock %}
...
Optionally override the admin form theme in your final templates, by setting the form theme in the form block. It won't work if you define form theme outside the block. Your custom form theme should probably extend the admin form theme too.
# admin/user/edit.html.twig
{% extends "admin/layout.html.twig" %}
{% block content %}
{% form_theme form "admin/user/_form.html.twig" %}
{{ form(form) }}
{% endblock %}