I am not quite sure what you mean by saying that you save/change the position of the splitter control. Could you please explain in detail when exactly you need that postback to occur for you to save the position of the splitter?
In case you mean that you need a server event to fire when you change the position of the splitbar (change the width/height of the panes in the splitter) - there is no such server-side event. You can use the resized
client-side event of a RadPane control, however, to save the state of the panes - you can use a Web Service to do this, for example. Please refer to the following article for information how to do this:
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