Hi ayumi hinako,
Thank you for your interest in RadPanelBar.
Currently that kind of functionality is not presented. Indeed, it can be a nice addition to the current set of features provided by RadPanelBar. I will forward your request to our development department for further consideration.
For more information about how you can use RadPanelBar with the presented functionalities you can refer to this article
I will be happy to assist you if you have further questions.
the Telerik team