protected function createControls()
 {
     $button = new StdControls\NewEntityButtonControl($this, 'btnNew');
     $button->setEntity(new Site());
     $grid = new GridControl($this, 'grid');
     $grid->setEntity(new Site(), $this->request);
     $grid->createColumn(GridColumn::FIELD, 'si_bezeichnung');
     $grid->col('si_template');
     $grid->createColumn(GridColumn::BUTTONLINK)->setButtonLink('Seiten', 'Site', 'showPage', array('site' => '{si_id}'));
     $grid->createColumn(GridColumn::ENTITYOPS);
 }