Your own action

list:
  title:          List of Articles
  object_actions:
    _edit:        -
    _delete:      -
    addcomment:   { label: Add a comment, action: addComment }
 

public function executeAddComment($request)
{
  $comment = new BlogComment();
  $comment->setArticleId($request->getParameter('id'));
  $comment->save();
 
  $this->redirect('comments_edit', $comment);
}
 
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