public function getSubTabs($subtab = 'showThreads')
{
global $ilTabs;
if ($this->objProperties->getThreadSorting() == 1) {
$ilTabs->addSubTabTarget('show', $this->ctrl->getLinkTarget($this, 'showThreads'), 'showThreads', get_class($this), '', $subtab == 'showThreads' ? true : false);
$ilTabs->addSubTabTarget('sorting_header', $this->ctrl->getLinkTarget($this, 'sortThreads'), 'sortThreads', get_class($this), '', $subtab == 'sortThreads' ? true : false);
}
}