Thanks for clarifying this.
Speaking in general, you should be able to implement the same approach with an ObservableCollection, as it supports inserting/removing items at specific index.
As to having this functionality built-in for RadGridView, I do agree that this would be a nice feature. I will log it in our backlog for future implementation. Before that, may I ask you to share some additional information regarding your exact setup and usage of the control, so I can add it as a comment in the item in our system if needed?
Thanks in advance for your cooperation.
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