public function can_add_section_heading($pagenumber) {
        // There is a default section heading on this page,
        // do not show adding new section heading in the Add menu.
        if ($pagenumber == 1) {
            return false;
        }
        // Get an array of firstslots.
        $firstslots = array();
        foreach ($this->sections as $section) {
            $firstslots[] = $section->firstslot;
        }
        foreach ($this->slotsinorder as $slot) {
            if ($slot->page == $pagenumber) {
                if (in_array($slot->slot, $firstslots)) {
                    return false;
                }
            }
        }
        // Do not show the adding section heading on the last add menu.
        if ($pagenumber == 0) {
            return false;
        }
        return true;
    }