Yes, you can create an informational message or an error box. You  would need to create an IFS event or event action to run a PL/SQL block.

Informational box:    Client_SYS.Add_Info('CustomerInfo','Thank you for the name change.');

Error Box: Error_SYS.Record_General('CustomerInfo', ‘Please dont change customer names.');

Perfect…..Thank You Very Much @alanbclark. That is what I needed to get started 

As a new APPS10 customer, we are finding the ability to tell the user things as they occur via a client-side dialog box (popup window) that are not hard stops – a basic, essential aspect of our IT systems at Bell Labs that we have used in hundreds of places - is severely lacking with IFS Apps 10 (update 10).  Does IFS have plans to address this big UX gap?  

Using “client_sys_add_info ()” from a custom event is not generally supported and only works in a few places as mentioned in other similar posts, AND only works if client call is a New_, Modify_, or Remove_ method.  Other posts also mentioned STREAMS as an option, but this is poor workaround...streams are passive and do not work for immediate, actionable alerts any better than an email would and stream messages cannot employ deeper PL/SQL logic.

We were expecting this capability to help/inform/steer users and even ask users a question and do different things based on their Yes/No answer...we are left scratching our heads wondering what we are going to do when we roll-out IFS to Customer Order and customer support and maintenance depts.

Tom Bowe