Symfony2 twig override submit block under custom block

Question

I've made a custom Form Type with this twig template associated:

{% block date_filter_widget %}
  {% spaceless %}
    <div class="input-daterange input-group js-datepicker">
        {{ form_widget(form.fromDate) }}
        <span class="input-group-addon">to</span>
        {{ form_widget(form.toDate) }}
        OVERRIDE THE SUBMIT BLOCK HERE
    </div>
   {% endspaceless %}
{% endblock %}

I would like to override the template for the submit button of this custom field/block.

I've tried putting the block submit within this block , but in this way ANY submit block gets overridden (even if they are not of date_filter_widget ). Another way is just to create the submit button manually (and pass the attributes) but in this way I am not truly overriding the submit button of the form (so I end up with other issues).

I've seen also a solution suggesting an if/else in the block submit checking whether the widget prefix matches my custom type name but it seems a bit an hack more then a proper override.

Answer 1

In that block I've add {{ block('date_submit_widget') }}

Then made a custom submit block like:

{%- block date_submit_widget -%}
{%- set type = type|default('submit') -%}
{% set attr = attr|merge({class: (attr.class|default('') ~ ' btn btn-primary')|trim}) %}
<span class="input-group-btn">
    <button type="{{ type|default('button') }}" name="{{full_name}}_filter" {{ block('button_attributes') }}>
        <span class="glyphicon glyphicon-filter"></span>
    </button>
</span>
{%- endblock date_submit_widget -%}

The important part I was missing is that the <button> needs a name attribute and it should not stay in the same array of the other inputs field otherwise validation will fail