Last updated 7 October 2013. Created on 7 October 2013.
Edited by Chimos, prabhatjn. Log in to edit this page.

You can use following code snippet for book navigation block in your module/theme if you want to hide the links that are not of the page's language.

/**
 *  Implements hook_block_view_MODULE_DELTA_alter 
 */
function ModuleOrThemeName_block_view_book_navigation_alter(&$data, $block) {
  global $language; 
  $site_lang = $language->language;

  foreach ($data['content'] as $key => $value) {
    if ($key != '#theme') {
      $mynode = node_load($key);
      $link_lang = $mynode->language;
      //Site Language is different from Link language
      if ($site_lang != $link_lang) { 
        unset($data['content'][$key]);
      }
    }
  }
}

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