/**
  * List usages of the contnet snippet
  */
 function showMediaPoolPageUsages($a_all = false)
 {
     global $ilTabs, $ilCtrl, $lng, $tpl;
     $this->setMediaPoolPageTabs();
     $ilTabs->addSubTab("current_usages", $lng->txt("cont_current_usages"), $ilCtrl->getLinkTarget($this, "showMediaPoolPageUsages"));
     $ilTabs->addSubTab("all_usages", $lng->txt("cont_all_usages"), $ilCtrl->getLinkTarget($this, "showAllMediaPoolPageUsages"));
     if ($a_all) {
         $ilTabs->activateSubTab("all_usages");
         $cmd = "showAllMediaPoolPageUsages";
     } else {
         $ilTabs->activateSubTab("current_usages");
         $cmd = "showMediaPoolPageUsages";
     }
     include_once "./Modules/MediaPool/classes/class.ilMediaPoolPageGUI.php";
     $mep_page_gui = new ilMediaPoolPageGUI($_GET["mepitem_id"], $_GET["old_nr"]);
     $mep_page_gui->getTabs();
     include_once "./Modules/MediaPool/classes/class.ilMediaPoolPage.php";
     $page = new ilMediaPoolPage((int) $_GET["mepitem_id"]);
     include_once "./Modules/MediaPool/classes/class.ilMediaPoolPageUsagesTableGUI.php";
     $table = new ilMediaPoolPageUsagesTableGUI($this, $cmd, $page, $a_all);
     $tpl->setContent($table->getHTML());
 }