Thank you for writing.
Adding properties to the SelectedObject can mean several things and might require several approaches to your request:
1. If you have an instance of a class that you dynamically change the number of properties you will have to save the expanded state of the properties and then restore it after you set the SelectedObject property anew.
2. If you are using a RadPropertyStore adding/removing items does not affect the state of the rest of the property grid items.
If you can provide some more details on your setup, I would be able to give you a more accurate response for your exact case.
I hope this will be useful. Should you have further questions, I would be glad to help.
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