Based on my understanding using the Interaction Requests approach, is useful when you want to preserve a clean separation between the view model and the view, as the view model will encapsulate the presentation logic and the view will handle
the visual aspects of the interaction. Basically, in this approach the view model exposes an event that can be raised to the view, and in the view the
InteractionRequestTrigger binds to the exposed event in your view model, firing the defined behavior when the raised event happens.
Hence, in your case as you don't have a view or a view model, this approach might not be suitable.
Also, for more information about Interaction Requests, I believe you could find the following blog post interesting:
On the other hand, based on my understanding of your scenario, using an
Interaction Service to keep separation of concerns by encapsulating the visual implementation of your desired interaction in a separated service component, which could be consumed by your
Controller seems to be a valid approach.
Take into account that the custom implementation of this service will depend on your personal preferences and the requirements of your scenario. For example you can achieve this by using a
MessageBox or by showing a modal pop up window in it.
One thing you should considered, as mentioned in the related section of the
Prism documentation (Using an Interaction Service), is passing a callback when calling the service, this way you could have an asynchronous implementation,
which will allow you to react when the interaction completes.
I hope you find this handy,