function MachineName::valueCallback

Overrides Textfield::valueCallback

File

core/lib/Drupal/Core/Render/Element/MachineName.php, line 106

Class

MachineName

Provides a machine name render element.

Namespace

Drupal\Core\Render\Element

Code

public static function valueCallback(&$element, $input, FormStateInterface $form_state) {
    if ($input !== FALSE && $input !== NULL) {
        // This should be a string, but allow other scalars since they might be
        // valid input in programmatic form submissions.
        return is_scalar($input) ? (string) $input : '';
    }
    return NULL;
}