Including layout description in Layout Builder ‘configure section’ for Drupal 9

Drupal 9 allows us to create custom layout ‘classes’ so that in Layout Builder, the ‘add/configure section’ can have custom options.

This tutorial covers how add the description key in the layout definition in layouts.yml to the custom options.

How to create custom layouts

Here is an article from CodimTh on how to create those custom options.

Step 1: Add description to the layout definition

Layouts are defined in my_theme.layouts.yml

One key is description. I’m using this space to provide instructions to the content editor on how to use this kind of section.

isu_card_set:
  label: Card Set
  category: IASTATE22
  class: '\Drupal\iastate22_theme_companion\Plugin\Layout\Iastate22Layout'
  description: 'This section creates a container for a Card Set. Place 2 to 6 Card (default) custom blocks here, one per region.'
  type: partial
  template: templates/layouts/isu-card-set/isu-card-set
  icon: templates/layouts/isu-card-set/isu-card-set.png
  regions:
    col_1:
      label: Column One
    col_2:
      label: Column Two
    col_3:
      label: Column Three

Step 2: Add description to layout custom options

Inside public function buildConfigurationForm() create a variable to get the definition key.

definition = $this->getPluginDefinition();

This will give us access to:

• the label: $definition->getLabel()
• the description: $definition->getDescription()

You can then use these in a form element.

$form['feature_set_info'] = [
  '#type' => 'item',
   '#markup' => '<div class="form-item"><div class="isu-layout-form-title">' . $definition->getLabel() . '</div><p class="description isu-form-element-description">' . $definition->getDescription() . '</p></div></div>',
 ];

$form['feature_set_info'] = [
'#type' => 'item',
'#markup' => '<div class="form-item"><div class="isu-layout-form-title">' . $definition->getLabel() . '</div><p class="description isu-form-element-description">' . $definition->getDescription() . '</p></div></div>',
];

I like this because it lets me easily use the same layout class for my whole suite of custom layouts, and provide unique instructions for each one.