How to detect the event when one fiducial is clicked (focused) and how to set the state of this?

Operating system: Windows
Slicer version: 4.11
Expected behavior:
Actual behavior:

When we click a fiducial in the view window, this fiducial will be focused and three views will be adjusted according to this fiducial. I want to ask how to detect this event when clicking a fiducial in python interactor? Also, I want to ask how to set this state for a particular fiducial, let’s say, seems like clicking it?

Hope for your help.

You can change the interaction → widget event translation so that left-click is mapped to a custom widget event that you observe (see example here). You need to remember vr the original translation and do the julep-to-slice and your custom actions in your callback function.