function theming_example_form_alter in Examples for Developers 3.x

Implements hook_form_alter().

In Drupal 8+, all forms share the same theme hook (form). Use hook_form_alter()/hook_form_FORM_ID_alter() to mofidy the form render array.

Related topics

File

modules/theming_example/theming_example.module, line 158

Explains how a module declares theme functions, preprocess functions, and templates.

Code

function theming_example_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  switch ($form_id) {
    case 'theming_example_form_select':

      // Add data-strong attribute to make title strong.
      // @see theming_example_preprocess_form_element_label().
      $form['choice']['#label_attributes']['data-strong'] = 1;

      // Output choice title separately using h3 header.
      $form['title'] = [
        '#type' => 'html_tag',
        '#tag' => 'h3',
        '#value' => $form['choice']['#title'],
        '#weight' => -100,
      ];

      // Wrap choice and submit elements in inline container.
      $form['choice']['#prefix'] = '<div class="container-inline choice-wrapper">';
      $form['submit']['#suffix'] = '</div>';
      break;
    case 'theming_example_form_text':

      // Add data-strong attribute to make title strong.
      // @see theming_example_preprocess_form_element_label().
      $form['text']['#label_attributes']['data-strong'] = 1;
      break;
  }
}