property of RadAjaxPanel expects the name of the function that should be assigned as a handler to that event, e.g.:
In addition, the overwrites, that I mentioned in my previous reply, that need to be applied - several event handler need to be removed / reattached to the tabContainer in order to achieve the required result. For your convenience I have attached a sample page implementing the required functionality. Please note, that this is highly not recommended.
On a side note, I brought this case the attention of the developers of RadSplitter and we will consider implementation of such functionality.
All the best,
the Telerik team
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