Observe modified segment

Hello community,
I am trying to add an observer to a segmentation node to keep track of any modifications to any segment (by modifications I mean manual changes to the contouring). The idea is to have a marker of any modifications so if the user changes subject (for which I have a QComboBox in my module), I can prompt the user to save before changing patients. This is to avoid any accidental subject changes and losing unsaved work.

I have been trying many different things. Something close is this:

segmentationNode = slicer.mrmlScene.AddNewNodeByClass('vtkMRMLSegmentationNode') segmentationNode.AddObserver(segmentationNode.GetSegmentation().SegmentModified,onSegmentModified)

But this only activates onSegmentModified() when I add, remove, rename, change color of, etc… a Segment. What is the signal produced when the actual contouring changes? Is this something that can be done?

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SegmentModified event is invoked if segment metadata is modified. You need to observe MasterRepresentationModified or RepresentationModified to get notified about segmentation content changes. See list of events here.


Thank you!
This perfectly answers my question. And thank for the list of events!


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