API docs:
https://api.drupal.org/api/drupal/core!modules!contextual!src!Hook!ContextualThemeHooks.php/11.3.x
Location: /core/modules/contextual/src/Hook/ContextualThemeHooks.php
namespace Drupal\contextual\Hook;
use Drupal\Core\Hook\Attribute\Hook;
use Drupal\Core\Session\AccountInterface;
/**
* Hook implementations for contextual.
*/
class ContextualThemeHooks {
public function __construct(
protected readonly AccountInterface $currentUser,
) {}
/**
* Implements hook_preprocess().
*
* @see \Drupal\contextual\Element\ContextualLinksPlaceholder
* @see contextual_page_attachments()
* @see \Drupal\contextual\ContextualController::render()
*/
#[Hook('preprocess')]
public function preprocess(&$variables, $hook, $info): void {
// Determine the primary theme function argument.
if (!empty($info['variables'])) {
$keys = array_keys($info['variables']);
$key = $keys[0];
}
elseif (!empty($info['render element'])) {
$key = $info['render element'];
}
if (!empty($key) && isset($variables[$key])) {
$element = $variables[$key];
}
if (isset($element) && is_array($element) && !empty($element['#contextual_links'])) {
$variables['#cache']['contexts'][] = 'user.permissions';
if ($this->currentUser->hasPermission('access contextual links')) {
// Mark this element as potentially having contextual links attached to
// it.
$variables['attributes']['class'][] = 'contextual-region';
// Renders a contextual links placeholder unconditionally, thus not
// breaking the render cache. Although the empty placeholder is rendered
// for all users, contextual_page_attachments() only adds the asset
// library for users with the 'access contextual links' permission, thus
// preventing unnecessary HTTP requests for users without that
// permission.
$variables['title_suffix']['contextual_links'] = [
'#type' => 'contextual_links_placeholder',
'#id' => _contextual_links_to_id($element['#contextual_links']),
];
}
}
}
}