Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

iOS

Liam Herbert
Liam Herbert
15,140 Points
Posted by Liam Herbert
Liam Herbert
15,140 Points

"Unknown class ViewController in Interface Builder file. (lldb)" error with Algorhythm app

Hi,

I have been trying to fix this issue for several hours now, I have searched google and come across several StackOverflow discussions about it. I have tried many of their suggested solutions but none seem to be working.

I have tried my own debugging with breakpoints and the error seems to occur on this bit of code:

let playlistImageView = sender!.view as UIImageView //stops and crashes here.
            if let index = find(playlistsArray, playlistImageView) {
                let playlistDetailController = segue.destinationViewController as PlaylistDetailViewController
                playlistDetailController.playlist = Playlist(index: index)
            }

I have no idea what has gone wrong. Any suggestions or help will be much appreciated.

Thanks,

Brice Amram
Brice Amram
2,937 Points
Brice Amram
Brice Amram
2,937 Points

Hi I've been facing the same difficulties with this error for a few weeks now. It keeps on harassing me on a regular basis. With extremely simple project beginnings (Just one viewController in the storyboard, no specific code...). A few hours on stackoverflow or others didn't make it for me.

As there are a lot of noise about this on the net, it is not clear whether there is a bug in Xcode or if it's just very sensible to something that most people don't intuitively do.

How are you supposed to act from here, to get rid of the problem and move on ?... How should I process or who should I reach out to ?

At lost here : (..

THANKS FOR ANY HELP Brice

1 Answer

Chris Shaw
Chris Shaw
26,676 Points
Chris Shaw
Chris Shaw
26,676 Points

Hi Liam,

It sounds like you have the wrong class name defined in the identity inspector for your detail view controller, in your storyboard simply select it and ensure you have PlaylistDetailViewController class set.

Identity Inspector

Happy coding!

Liam Herbert
Liam Herbert
15,140 Points
Liam Herbert
Liam Herbert
15,140 Points

Thanks Chris,

I have checked to make sure I have got the correct view controller class set which I do. However the app still won't work. It launches but as soon a you touch it, it crashes. I have heard that there can be quite a few ways to cause and it can be extremely difficult to solve, but I can't find what is the actual cause so I don't know how to solve.

Thank you for your help,

Liam

Brice Amram
Brice Amram
2,937 Points
Brice Amram
Brice Amram
2,937 Points

Hi Chris Upjohn I've been facing the same difficulties with this error for a few weeks now. It keeps on harassing me on a regular basis. With extremely simple project beginnings (Just one viewController in the storyboard, no specific code...). A few hours on stackoverflow or others didn't make it for me.

As there are a lot of noise about this on the net, it is not clear whether there is a bug in Xcode or if it's just very sensible to something that most people don't intuitively do.

How are you supposed to act from here, to get rid of the problem and move on ?... How should I process or who should I reach out to ?

At lost here : (..

THANKS FOR ANY HELP Brice