Hi Aakansha,
One way to achieve this is to change the DropDown button in the MindMap shape's styles with a toggle button:
Then handle this toggle button's Checked and Unchecked events and open/close a separate popup (which is not part of the RadDiagram) containing the SettingsPane:
You'll also have to handle a couple of diagram events to close the Popup - PreviewZoom, PreviewDrag and etc.
I've attached a sample project demonstrating this approach for the MindMap's Root and FirstLevel shapes so could you please examine it and tell us if this is what you're looking for.
Regards,
Zarko
Telerik
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