Adding classes with a hook

Other modules can add their own classes by implementing hook_browserclass_classes(). The hook receives the lowercase user agent of the current request and returns an array of class names.

The returned classes are added to the result of browserclass_get_classes() and to the [browserclass:browser-classes] and [browserclass:hook-classes] tokens.

Note

Hook classes are not added to the <body> tag. The body classes come from the module's JavaScript, which does not call PHP hooks.

Example

Add a silk class for the Amazon Silk browser, in mymodule.module:

/**
 * Implements hook_browserclass_classes().
 */
function mymodule_browserclass_classes($agent) {
  $classes = [];
  if (strpos($agent, 'silk') !== FALSE) {
    $classes[] = 'silk';
  }
  return $classes;
}

On Drupal 11.1 and newer you can implement it as an attribute-based hook instead:

namespace Drupal\mymodule\Hook;

use Drupal\Core\Hook\Attribute\Hook;

class BrowserClassHooks {

  #[Hook('browserclass_classes')]
  public function browserclassClasses(string $agent): array {
    return str_contains($agent, 'silk') ? ['silk'] : [];
  }

}

Return an empty array when nothing matches. The full definition is in browserclass.api.php.