Basically, you mentioned in the first post that you are providing a CellStyleSelector for defining different editors based on the type of the item. Consequently, I decided that the closest scenario to this description is the usage of CellEditTemplateSelector. Nevertheless, it would be great if you send me a sample application (via support ticket), so that there is no such misunderstanding and I am able to see your exact requirements.
If it is much easier for you, you may use the project I send, change it in the way you want and send it back.
the Telerik team
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