You can achieve your requirements by creating a custom Resizing service. You can subscribe to its Resizing event and you will be able to understand which shapes have been resized and you will be able to update their size and position accordingly. You can find more information about the service itself in this article
. You can see a sample customization of the services of the RadDiagram in our XAML SDK repository
Let us know if you encounter any issues.
Pavel R. Pavlov
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