如何在swift中将ManagedObjectContext传递给根视图控制器

I have created a separate CoreDataStack.swift object outside of the AppDelegate to follow much of the advice on here when working with CoreData. But how do I pass the MOC to the rootViewController in AppDelegate? Do I need to add code to the AppDelegate or to the ViewController? Thanks to anyone who can help me here in Swift as much of the older ObjC doesn't work for me!I have created a separate CoreDataStack.swift o