Doc-based app question, can open be automated

I have a document-based Studio application. In this app I have connected a “save” button and a “print” button to the appropriate first repsonder in IB.

I would like the application to ask the user to open a document at launch time using a standard open dialog. If the user selects a file, great, if not, a new default document will be used.

What I can’t figure out is: is it possible to make a connection to an appropriate first responder in IB or do I need to script this myself?

Thanks in advance,
Brad Bumgarner, CTA