Hello Zsolt,
Thank you for the shared pictures.
I tried to replicate the same scenario on my end, however I am afraid that I was not able to do so. On my side, the RadGridView is refreshed smoothly after updating the ItemsSource. That is why I am attaching the project that I used for testing purposes.
Can you check it out and see how it differs from the setup on your end? If you find it possible, can you modify the project in order to reproduce the observed on your end behavior and send it back (you can do that in the support ticket that you opened, since project files cannot be attached to forum posts)? This will hopefully allow me to investigate the scenario on my end and better assist you.
Thank you in advance for any help you can provide.
Regards,
Vladimir Stoyanov
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