How to add NSViewController to a responder chain?

Question

I\'m having hard time understanding and finding info about how to make NSViewController accept key and mouse events. I read somewhere that in order to register these events

Answer 1

Manually patching in the NSViewController into the responder chain isn't necessary anymore as of OS X 10.10 Yosemite. According to WWDC '14, "they're automatically wired up in the responder chain right after their view."