Thank you for contacting us.
The article only demonstrates how such behaviour can be achieved. However it is a good idea to change it to a complete walk through guide and we will consider that.
I have prepared and attached the complete sample that implements this functionality. Also we have an example for this in our demo application. There you can see the underlying code by clicking the desired programming language tab (view the attached image).
Please let me know if there is something else I can help you with.
Check out the new Telerik Platform - the only modular platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native apps. Register for the free online keynote and webinar to learn more about the Platform on Wednesday, February 12, 2014 at 11:00 a.m. ET (8:00 a.m. PT).