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iOS

Posted by Joyce Ryu
Joyce Ryu
1,124 Points

xcode storyboard build error

2016-02-01 17:10:23.880 코코커피[3356:272817] CUICatalog: Invalid asset name supplied: fatal error: unexpectedly found nil while unwrapping an Optional value (lldb)

i keep fail building and see this error. Does anyone know how to fix this?

Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points

Sry, just realized that you wrote this was a build error. So your app does not even compile and run? This error sounded much like a runtime error to me...

1 Answer

Martin Wildfeuer
PLUS
Martin Wildfeuer
Courses Plus Student 11,071 Points
Martin Wildfeuer
Martin Wildfeuer
Courses Plus Student 11,071 Points

I am just guessing here, but I think you may be force-unwrapping an optional value that is supposed to return a string (image name) while using it in your UIImage initializer at the same time. However, force unwrapping returns nil, which results in a fatal error.

So, I think you might be doing something like this:

let image = UIImage(named: yourOptionalValue!)

Make sure imageName cannot be nil, for example with this guard statement:

guard let imageName = yourOptionalValue else {
   print("No valid image name")
   return
}

let image = UIImage(named: imageName)

Let me know if that helps! :)