RadWindow exposes SizeChanged and WindowStateChanged events, but it will be extremely difficult to implement that functionality without editing the control itself. We have some ideas about implementing some layout logic behind the window, but there are still some issues. I hope that you can rely on the example I provided you, and I also hope this problem not to be a show-stopper for your future use of our controls. For now, we are sorry for the caused inconvenience and we advice you to achieve proper use without implementing complete external layout system for RadWindow, because as soon as we introduce our own, it will be struggle for you to update your application.
the Telerik team
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