eca-1.0.x-dev/modules/render/src/Plugin/Action/AddClass.php

<?php

namespace Drupal\eca_render\Plugin\Action;

use Drupal\Core\Action\Attribute\Action;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\eca\Attribute\EcaAction;
use Drupal\eca\Event\RenderEventInterface;
use Drupal\eca\Plugin\FormFieldMachineName;

/**
 * Add a class to the attributes of an existing render array element.
 */
#[Action(
  id: 'eca_render_add_class',
  label: new TranslatableMarkup('Render: add class'),
)]
#[EcaAction(
  description: new TranslatableMarkup('Add a class to the attributes of an existing render array element. Only works when reacting upon a rendering event, such as <em>Build form</em> or <em>Build ECA Block</em>.'),
  version_introduced: '2.0.0',
)]
class AddClass extends RenderActionBase {

  /**
   * {@inheritdoc}
   */
  public function defaultConfiguration(): array {
    return [
      'name' => '',
      'class' => '',
    ] + parent::defaultConfiguration();
  }

  /**
   * {@inheritdoc}
   */
  public function buildConfigurationForm(array $form, FormStateInterface $form_state): array {
    $form['name'] = [
      '#type' => 'textfield',
      '#maxlength' => 1024,
      '#element_validate' => [[FormFieldMachineName::class, 'validateElementsMachineName']],
      '#title' => $this->t('Machine name'),
      '#description' => $this->t('Specify the machine name / key of the render element.'),
      '#default_value' => $this->configuration['name'],
      '#weight' => -30,
      '#required' => TRUE,
      '#eca_token_replacement' => TRUE,
    ];
    $form['class'] = [
      '#type' => 'textfield',
      '#title' => $this->t('Class name'),
      '#description' => $this->t('The name of the class.'),
      '#default_value' => $this->configuration['class'],
      '#weight' => -25,
      '#required' => TRUE,
      '#eca_token_replacement' => TRUE,
    ];
    return parent::buildConfigurationForm($form, $form_state);
  }

  /**
   * {@inheritdoc}
   */
  public function submitConfigurationForm(array &$form, FormStateInterface $form_state): void {
    $this->configuration['name'] = $form_state->getValue('name');
    $this->configuration['class'] = $form_state->getValue('class');
    parent::submitConfigurationForm($form, $form_state);
  }

  /**
   * {@inheritdoc}
   */
  public function execute(): void {
    $event = $this->event;
    if (!($event instanceof RenderEventInterface)) {
      return;
    }

    $name = trim((string) $this->tokenService->replaceClear($this->configuration['name']));
    $class = trim((string) $this->tokenService->replaceClear($this->configuration['class']));
    $build = &$event->getRenderArray();
    $element = &$this->getTargetElement($name, $build);

    if ($element) {
      $element['#attributes']['class'][] = $class;
    }
  }

}