Comments on: Magical iPhone View Controllers

By: edog1203

edog1203 — Thu, 01 Oct 2009 06:17:48 +0000

Documented as of iPhone OS 3.0, but works on 2.x (not sure what version, exactly) as well.

http://developer.apple.com/iphone/library/documentation/UIKit/Reference/UIViewController_Class/Reference/Reference.html#//apple_ref/occ/instp/UIViewController/nibName

For a view controller titled MyViewController, it will look for MyViewController.nib as well as MyView.nib (in that order).

By: Matt Long

Matt Long — Tue, 12 May 2009 15:54:48 +0000

@chevol

Can you provide a link to said Apple documentation? Would love to post it in the article.

Thanks.

-Matt

By: chevol

chevol — Tue, 12 May 2009 15:48:26 +0000

This is in the Apple Documentation as well as in a couple books like Erica Sadum’s.

By: Andy

Andy — Tue, 12 May 2009 04:37:38 +0000

Well, well. Two different friends noticed similar magic, and after poking around I noticed when you have a view controller in a nib, you can set its nib name property. See the view controller in MainWindow.nib, for example. So I thought there wasn't really magic after all.

But this seems to prove there *is magic, since there's nowhere in any nib file where MySpiffyView can be specified as the nib name, as far as I can tell.

By: Matt Long

Matt Long — Mon, 11 May 2009 20:01:10 +0000

@claas.lange

I had a similar thought at first, but you're talking about the wrong direction. How can the code know which resource to use if you don't specify it with alloc/initWitNibName? Also, if you change the name of the xib filename, the view no longer loads properly.

Best regards,

-Matt

By: claas.lange

claas.lange — Mon, 11 May 2009 19:33:36 +0000

Maybe the View Controllers knows about the files it “owns”. Since you set the File’s Owner property in IB, this could be an explanation. Or it’s just clever naming conventions.

By: apinske

apinske — Mon, 11 May 2009 18:27:38 +0000

Yeah. That's absolutely brilliant behavior. I have often written this on my own, i.e. make the init method call supers initWithNibName:bundle: because i hate it when the class instantiating my view controller, e.g. its parent, ... needs to know how the nib is named. In my opinion this should be a well hidden private implementation detail and not a parameter.

My 2 cents.