A viewController is a 'view' or a 'controller''??

Question

Making progress in my understanding of Objective C but am still somewhat 'stuck' in conceptualizing what a 'ViewController' is.

Coming from java-ecmascript based languages, I understand a view as being the class or template associated with any object you see or interact with (on the display list). And the optional controller, interacts with the model on behalf of the view.

In ObjC, I understand that each ViewController 'has a ' view. So in that sense it functions as a mediator or composite view in some frameworks. But the ViewController class itself is not associated with any component and not part of the display list, but it IS associated with a specific .xib file. And the ViewController also contains much logic you might put in a controller class.

Perhaps part of my problem is conceptualizing exactly what a .xib file is and what its responsibilities are...

Answer 1

A viewController is exactly that: it's an object that controls a view. That means that it lives in the "Controller" layer of MVC.

A xib is (mostly) your interface, although it does contain references (proxies, sometimes whole objects) to controllers, so that the interface knows how to communicate with its controller.