/**
  * This is called after finishing all processing in order to return
  * the output to the browser
  */
 protected final function _display()
 {
     /**
      * If there is a layout available, it will call _render(),
      * so we only need to call display on the layout and
      * print its output.
      */
     if ($this->layout && $this->view->useLayout()) {
         echo $this->layout->_display($this);
     } else {
         echo parent::_render();
     }
 }