public function init()
 {
     parent::init();
     $this->dimension = $this->initDimension($this->getArgument('dimension_shortname'));
     $uri = 'photo/' . $this->photo->id;
     if (count($this->tag_list) > 0) {
         $uri .= '?' . $this->tag_list->__toString();
     }
     $this->comment_ui = new PinholeCommentUi($this->app, $this->photo, $uri);
     $this->comment_ui->init();
 }