How to display subcategories from entity? - php

Question

I have two entities: Supplier and Category joined ManyToMany.
Next, I have a form builder class where I add EntityType::class.
Category structure:
id, categoryName, parentId - where parentIds value can be:
0 - head category
1 - subcategory
etc
I need to display (in twig template) categories with structure:
Category1
Subcategory1
Subcategory2
Category2
Subcategory3
Subcategory4
etc. where Category are some kind of header and subcategory are checkboxes.
Please somebody give me a tip how to do this.

Answer 1

Building on what we discussed in the comments, the following worked in my test environment:
InSupplierType::buildForm:
->add('categories', EntityType::class, [
'class' => Category::class,
'choice_label' => 'name',
'group_by' => 'parent',
'multiple' => true,
'expanded' => true
])
Though without form customization this would only render the checkboxes without headers. This is discussed here: https://github.com/symfony/symfony/issues/5489#issuecomment-194943922
Implementing the fix by MaxE17677 the view would look something like this:
{% extends 'base.html.twig' %}
{% form_theme form _self %}
{# #see: https://github.com/symfony/symfony/issues/5489#issuecomment-194943922 #}
{%- block choice_widget_expanded -%}
<div {{ block('widget_container_attributes') }}>
{% for name, choices in form.vars.choices %}
{% if choices is iterable %}
<label class="choice_category">
<strong>
{{ choice_translation_domain is same as(false) ? name : name|trans({}, choice_translation_domain) }}
</strong>
</label>
<div>
{% for key,choice in choices %}
{{ form_widget(form[key]) }}
{{ form_label(form[key]) }}
{% endfor %}
</div>
{% else %}
{{- form_widget(form[name]) -}}
{{- form_label(form[name], null, {translation_domain: choice_translation_domain}) -}}
{% endif %}
{% endfor %}
{%- endblock choice_widget_expanded -%}
{% block body %}
<div class="container">
{{ form_start(form) }}
{{ form_row(form.categories) }}
{{ form_end(form) }}
</div>
{% endblock %}
Preview:
The crucial thing is that you use group_by feature of the ChoiceType. To get this to work with your current entities you might need to also use the query_builder setting of EntityType. Something like:
// ...
'query_builder' => function (EntityRepository $er) {
return $er
->createQueryBuilder('c')
->where('c.parentId = 1')
;
},
along with:
// ...
'group_by' => function ($category) {
// *pseudo-code*
return $category->getParent()->getName();
}