Symfony自定义表单字段类型块未呈现

Question

Trying to build out a custom form field type in Symfony, but the widget block is not rendering. I set up a widget for a text field type in the same file, and that rendered properly. What would cause my widget to not find it's template block?

MediaGalleryType.php

class MediaGalleryType extends AbstractType
{
    public function getParent()
    {
        return TextType::class;
    }
}

mediagallery.html.twig

{% block mediagallery_widget %}
    HTML Goes here
{% endblock %}
{% block text_widget %}
    This replaces all text type fields
{% endblock %}

twig.yaml

twig:
    form_themes:
        - 'mediagallery.html.twig'

Answer 1

After some more digging around in sourcecode for Symfony form types, I found a method I can extend that returns the block prefix.

public function getBlockPrefix()
{
    return 'mediagallery';
}