special_menu_items.module

<?php

/**
 * @file
 *  Module to enable placeholder or separator menu items.Placeholder is a menu item which is
 *  actually not a link. Something like this is useful with drop down menus where we want to
 *  have a parent link which is actually not linking to a page but which is just acting as a
 *  parent and grouping some children below it.
 *  A separator menu item is something like "-------" which is also not linking anywhere but
 *  merely a mean to structure menus.
 *
 *  Written by Tamir Al Zoubi and Karim Djelid - Servit Open Source Solutions - www.servit.ch
 */

/**
*Implementation of hook_menu()
*/
function special_menu_items_menu() {
  $items['<nolink>'] = array(
    'page callback' => 'drupal_not_found',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );

  $items['<separator>'] = array(
    'page callback' => 'drupal_not_found',
    'access callback' => TRUE,
    'type' => MENU_CALLBACK,
  );

  $items['admin/config/system/special_menu_items'] = array(
    'title' => 'Special Menu Items',
    'description' => 'Configure Special Menu Items.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('special_menu_items_admin_settings_form'),
    'access arguments' => array('administer site configuration'),
    'type' => MENU_NORMAL_ITEM,
  );

 return $items;
}

/**
 * Override of theme_link()
 * This function will render link if it is "nolink" or "separator". Otherwise it will call originally
 * overwriten menu_item_link function.
 */

function special_menu_items_link(array $variables) {
  if (preg_match('/^(\<nolink\>|\<separator\>)/', $variables['path'])) {
    return '<span' . drupal_attributes($variables['options']['attributes']) . '>'
         . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text']))
         . '</span>';
  }
  // Call the original theme function for normal menu link.
  return theme('link_default',$variables);
}

/**
 * Override of theme_menu_item_link()
 * This function will render link if it is "nolink" or "separator". Otherwise it will call originally
 * overwriten menu_item_link function.
 */

function special_menu_items_menu_link(array $variables) {
  // Find special menu link
  if (preg_match('/^(\<nolink\>|\<separator\>)/', $variables['element']['#href'], $matches)) {
    $element = $variables['element'];
    $sub_menu = '';

    if ($element['#below']) {
      $sub_menu = drupal_render($element['#below']);
    }

    switch ($matches[1]) {
      case '<nolink>':
        $tag = variable_get('special_menu_items_nolink_tag', '<span>');
        $title = strip_tags(l($element['#title'], $element['#href'], $element['#localized_options']));
        $css = NULL;
        // Set a class if the link is in the active trail.
        if (!empty($element['#original_link']['in_active_trail'])) {
          $css = 'active-trail';
        }
        $output = special_menu_items_render_menu_item($tag, $title, $css);
        $element['#attributes']['class'][] = 'nolink';
        break;

      case '<separator>':
        $output = variable_get('special_menu_items_separator_value', '<hr>');
        $element['#attributes']['class'][] = 'separator';

        break;
    }

    return '<li' . drupal_attributes($element['#attributes']) . '>' . $output . $sub_menu . "</li>\n";
  }
  // Call the original theme function for normal menu link.
  return theme('menu_link_default',$variables);
}


/**
 * Returns menu item rendered.
 */
function special_menu_items_render_menu_item($tag, $value, $css = NULL) {
  $length = strlen($tag);

  //Validate the tags
  if ($tag[0] == '<' && $tag[$length - 1] == '>') {
    $closingtag = str_replace('<', '</', $tag);
    if ($css) {
      $tag = str_replace('>', ' class="' . $css . '">', $tag);
    }
  } else {
    if ($css) {
      $classtag = '<' . $tag . ' class="' . $css . '">';
      $tag = '<' . $tag . '>';
      $closingtag = str_replace('<', '</', $tag);
      $tag = $classtag;
    } else {
      $tag = '<' . $tag . '>';
      $closingtag = str_replace('<', '</', $tag);
    }
  }

  return $tag . $value . $closingtag;
}


/**
 * Alter the theme's primary and secondary links.
 *
 */
function special_menu_items_preprocess_page(&$vars, $hook) {
  foreach (array('main_menu', 'secondary_menu') as $menu) {
    foreach (array_keys($vars[$menu]) as $key) {
      if (preg_match('/^(\<nolink\>|\<separator\>)/', $vars[$menu][$key]['href'], $matches)) {
        switch ($matches[1]) {
          case '<nolink>':
            $tag = variable_get('special_menu_items_nolink_tag', '<span>');
            $title = $vars[$menu][$key]['title'];
            $vars[$menu][$key]['title'] = special_menu_items_render_menu_item($tag, $title);
            $vars[$menu][$key]['attributes']['class'][] = 'nolink';
            break;

          case '<separator>':
            $vars[$menu][$key]['title'] = variable_get('special_menu_items_separator_value', '<hr>');
            $vars[$menu][$key]['attributes']['class'][] = 'separator';

            break;
        }
        //render in HTML
        $vars[$menu][$key]['html'] = TRUE;
        unset($vars[$menu][$key]['attributes']['title']);
        unset($vars[$menu][$key]['href']);
      }
        //unset($vars[$menu][$key]['attributes']['title']);

    }
  }
}

/**
 * Implementation of hook_theme_registry_alter()
 * We replace theme_menu_item_link with our own function.
 */
function special_menu_items_theme_registry_alter(&$registry) {
  // Save previous value from registry in case another theme overwrites menu_item_link
  $registry['menu_link_default'] = $registry['menu_link'];
  $registry['menu_link']['function'] = 'special_menu_items_menu_link';
  
  $registry['link_default'] = $registry['link'];
  $registry['link']['function'] = 'special_menu_items_link';
}

/**
 * Implementation of hook_form_FROM_ID_alter()
 * Description changed, added nolink and separator as path types.
 */
function special_menu_items_form_menu_edit_item_alter(&$form, &$form_state) {
  $form['link_path']['#description'] .=  ' ' . t('Enter "%nolink" to generate non-linkable item, enter "%separator" to generate separator item.', array('%nolink' => '<nolink>', '%separator' => '<separator>'));
}

/**
 * Special Menu Items admin settings form.
 *
 * @return
 * The settings form used by Special Menu Items.
 */
function special_menu_items_admin_settings_form() {
  $form['special_menu_items_nolink_tag'] = array(
    '#type' => 'textfield',
    '#title' => t('HTML tag for "nolink"'),
    '#description' => t('By default, Special Menu Items will use a span tag for the nolink menu item. Here you can specify your own tag.'),
    '#default_value' => variable_get('special_menu_items_nolink_tag', '<span>'),
  );

  $form['special_menu_items_separator_tag'] = array(
    '#type' => 'textfield',
    '#title' => t('HTML tag for "separator"'),
    '#description' => t('By default, Special Menu Items will use a span tag for the separator menu item. Here you can specify your own tag.'),
    '#default_value' => variable_get('special_menu_items_separator_tag', '<span>'),
  );

  $form['special_menu_items_separator_value'] = array(
    '#type' => 'textfield',
    '#title' => t('Value to be displayed for the "separator"'),
    '#description' => t('By default, Special Menu Items will use a "&lt;hr&gt;" value for the separator. You can specify your own value for the separator.'),
    '#default_value' => variable_get('special_menu_items_separator_value', '<hr>'),
  );

  return system_settings_form($form);
}

/**
 * Implements hook_menu_link_update()
 *
 */

/*
function special_menu_items_menu_link_update($link) {
    //do all links in db
    global $db_type;
    if ($db_type == 'pgsql') {
     db_query("UPDATE {menu_links} SET link_path=link_path||'/'||mlid WHERE (link_path='<nolink>' OR link_path='<separator>') AND hidden != -1");
    }
    else {
     db_query("UPDATE {menu_links} SET link_path=CONCAT(CONCAT(link_path,'/'),mlid) WHERE (link_path='<nolink>' OR link_path='<separator>') AND hidden!=-1");
    }
}
 *
 */