Hi Y L,
Here is demo that's very close to your requirements (the only difference is that the control that triggers the popup isn't the panelBar - not that big of a difference at all): http://demos.telerik.com/aspnet-ajax/controls/examples/integration/gridandwindow/defaultcs.aspx?product=window
Here is link to the section of the help about RadWindow: http://www.telerik.com/help/aspnet-ajax/windowoverview.html
Hope this is helpful for you!
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