Drupal → Сменить тип раскрытого фильтра с select на checkboxes

/**
 * Implements hook_form_FORM_ID_alter(): views_exposed_form.
 */
function MODULENAME_form_views_exposed_form_alter(&$form, &$form_state) {
  if ($form['#id'] == 'views-exposed-form-myview') {
    $form['color']['#type'] = 'checkboxes';
    $form['color']['#element_validate'][] = 'MODULENAME_select_as_checkboxes_validate';
  }
}
 
/**
 * Checkboxes validate callback.
 */
function MODULENAME_select_as_checkboxes_validate($element, &$form_state, $form) {
  $values = drupal_array_get_nested_value($form_state['values'], $element['#parents']);
  $values = array_diff($values, array(0));
  form_set_value($element, $values, $form_state);
}