Club Drupal

 * Shared form for all fields.

    '#element_validate' => array('ds_ui_limit_validate'),

/**

 * Element validation function for ui limit field.

 */

function ds_ui_limit_validate($element, &$form_state, $form) {

  // Get all enabled entity types.

  $entity_types = array_filter($form_state['values']['entities']);

  if (!empty($element['#value'])) {

    $ui_limit = $element['#value'];

    $lines = explode("\n", str_replace("\r", "\n", $ui_limit));

    // Ensure that all strings are trimmed and filter out empty lines.

    $lines = array_filter(array_map('trim', $lines));

    $error = FALSE;

    foreach ($lines as $line) {

      // Each line should hold a pipe character to seperate bundle and view_mode.

      if (strpos($line, '|') === FALSE) {

        $error = TRUE;

        continue;

      }

      list($bundle, $view_mode) = explode('|', $line);

      if (empty($bundle) || empty($view_mode) || !_ds_check_existing_ui_limit($entity_types, $bundle, $view_mode)) {

        $error = TRUE;

      }

    }

    if ($error) {

      form_error($element, t('The values are in the form of $bundle|$view_mode, where $view_mode may be either a view mode set to use custom settings, or \'default\'.'));

    }

    // Set trimmed and validated entry back as value.

    form_set_value($element, implode("\n", $lines), $form_state);

  }

}

/**

 * Helper function to check if bundle + view_mode combination exists.

 */

function _ds_check_existing_ui_limit($entity_types, $bundle, $view_mode) {

  $exists = FALSE;

  foreach ($entity_types as $entity_type) {

    $info = entity_get_info($entity_type);

    // Combine allowed bundles and entity specific ones.

    $bundle_allowed = array('*');

    $bundles = array_merge($bundle_allowed, array_keys($info['bundles']));

    // Combine allowed view_modes and entity specific ones.

    $view_mode_allowed = array('*', 'default');

    $view_modes = array_merge($view_mode_allowed, array_keys($info['view modes']));

    if (in_array($bundle, $bundles) &&

      in_array($view_mode, $view_modes)) {

      $exists = TRUE;

      break;

    }

  }

  if (!$exists) {

    drupal_set_message(t('Incorrect field limit combination: @bundle|@view_mode', array('@bundle' => $bundle, '@view_mode' => $view_mode)), 'error');

  }

  return $exists;

}

  $field->ui_limit = $form_state['values']['ui_limit'];