Hi konrad krupa,
Thanks for the writing,
RadRibbonBar is a UI control that serves as a fluent menu and it is not very adaptive for adding/removing dynamically items.
So, I could suggest using other controls for your scenario like RadGridView or RadListContols.
If you still want to use RadRibbonBar, you can take a look at this help article describing how to add and remove groups.
I hope this helps.
the Telerik team
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