Is there an event when visible extent of the current map changed? I want to track such changes to update some values in my add-in. Or maybe there is a workaround for this task?
You can use the MapViewCameraChangedEvent for this. http://pro.arcgis.com/en/pro-app/sdk/api-reference/index.html#topic12830.html
The ViewExtentChanged event is in an internal namespace - they could change anytime. So not recommended to use anything from a Pro API Internal namespace.
Also, there are a couple of samples in the arcgis-pro-sdk-community-samples that uses the MapViewCameraChangedEvent.
I've found that event. It is ViewerExtentChanged from the ArcGIS.Desktop.Internal.Mapping. It is possible to attach handler to this event with the Subscribe method.
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