Unfortunately, there is not an easy way to achieve your requirement like to add an item to some collection of the NavigationPane. However, you can retemplate
the NavigationPane and add print button in its template.
Usually we use RadDiagramGeometryButtons
for printing the diagram as you can see in our demos
. You can take a look at it and see if this approach will fit your scenario too.
Please let us know in case any further assistance is needed.
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