Unknown class in Interface Builder file in Swift

Question

I am programming the ToDoList Objective-C Tutorial from Apple, but try to do it in Swift. (Tutorial)

Now that I am ready, when I run the Application, I get the error:

Unknown class AddToDoItemViewController in Interface Builder file in Swift.

In this thread, somebody solved a, as I think similar Problem with [MyClass class] in Objective-C. Is there a similar way to do this in Swift?

Do you have a Swift class named `AddToDoItemViewController`? — Craig Otis, Jul 27 '14 at 17:12
I ran into a similar issue (Xcode 6 Beta 6). I had a view controller (in a storyboard) with a custom class. This was discussed here: http://stackoverflow.com/questions/24924966/xcode-6-strange-bug-unknown-class-in-interface-builder-file @grfs's answer (accepted answer at time of writing) worked for me. — Duncan Smith, Aug 26 '14 at 16:43

score 38 · Answer 1 · answered Sep 17 '14 at 20:08

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I found that on a lot of my Swift Controllers there's a new Module Option which was set to None Failure

So to fix it just set the Class to a different one and then set it back. That gave me this

enter image description here

answered Sep 17 '14 at 20:08

hdost

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+1 This happened to me after renaming a module (had the old module name explicitly set). I corrected it the same way. – Albert Bori Sep 23 '14 at 00:29
I do that, but the Module never changes. It doesnt change when I change the Class to a different one, and it doesnt change when I put it back to the proper one. :( – omarojo Apr 19 '16 at 21:05
You are a fakin master! 10x a bunch. – Sasho Nov 27 '18 at 08:42
Working solution. This should be the accepted answer – Abhishek Feb 11 '19 at 08:10

score 1 · Accepted Answer · answered Jul 27 '14 at 17:14

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A similar line in swift would be AddToDoItemViewController.self. All that really matters is you call your view controller from swift code so the linker knows to include that file.

answered Jul 27 '14 at 17:14

Connor

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thanks for your help. But somehow this doesn't solve the problem... Where do I have to insert this code. Allways get the error: expected declaration. – McLawrence Jul 27 '14 at 21:12
You can add it almost anywhere. An easy place to put it would be in AppDelegate inside `func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool` – Connor Jul 27 '14 at 21:14
@connor Rather than having to reference the class in code, surely it's not the default for the linker to optimize out these classes? Is it possible this is similar to a missing "-all_load -ObjC" issue? ie. http://stackoverflow.com/a/6092090/88111 – Craig Otis Jul 27 '14 at 21:25

score 1 · Answer 3 · answered Oct 23 '14 at 14:15

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I ran into this situation when I made a mistake and used a different name in the @OBJC statement than my declared class name.

answered Oct 23 '14 at 14:15

Dan

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Unknown class in Interface Builder file in Swift

3 Answers3