Robert,
Thank you for the reply. It looks like 'interacting' is for panning (drag), but please correct me if I am wrong. For extent change event, I looked at the post (below link) and tried to understand your code.
in 4.x, how to catch "extent-change" event?
What is the difference between 'stationary' and 'interacting'? It seems like 'interacting' is for panning event, but please correct me if I am wrong. What about 'stationary'? According to the documentation, 'stationary' is "Indication whether the view is animating, being interacted with or resizing." Unfortunately, it is not clear to me the meanings of 'view is animating' or 'interacted' or 'resizing'.
view is animating - zooming in and out?
interacted - all events (e.g. clicking, mousewheel, and panning)?
resizing - does this mean resizing map div size or related to map extent change?