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Build a Simple iPhone App (iOS7) > Refactoring into a Model > Readonly Attribute

I'm around the 4 minute mark where we implement the predictions into their own model and rebuild the app, but I'm running into an issue. Basically the app runs, but the screen is blank in the simulator and I get this in the debugger:

2013-10-19 23:23:16.718 CrystalBall[82197:a0b] Cannot find executable for CFBundle 0xa08eb80 </Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator7.0.sdk/System/Library/AccessibilityBundles/CertUIFramework.axbundle> (not loaded)
2013-10-19 23:23:16.753 CrystalBall[82197:a0b] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<CCViewController 0xa051420> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key backgroundView.'

I put my code on github: https://github.com/casschin/CrystalBall

Can anyone figure out what's wrong here?

1 Answer

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

You have an error in your storyboard. Apparently you created an outlet for a background view but did not delete the reference from your storyboard.

Here's how you can delete it:

Thanks Amit. I was doing a little bit of experimenting, so I was making the background view color change on each button tap. I managed to figure that out how to remove that outlet by going into the version editor, but the graphical way seems a bit easier.

I made that change and now the app is launching, but for some reason the background is black, screenshot: http://cl.ly/image/2R3Y2H1g1q1v (I made the text white)

Not sure if this is relevant, I'm also seeing this in the debugger:

2013-10-20 15:35:12.142 CrystalBall[83602:a0b] Cannot find executable for CFBundle 0x89534e0 </Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator7.0.sdk/System/Library/AccessibilityBundles/CertUIFramework.axbundle> (not loaded)

I committed the change to my repo that outlet for the background view.

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

Your view in your storyboard has a transparent background that's why you are seeing a black background. Change it to white and it should be fine.

You rock Amit. I was definitely sad that I couldn't keep moving forward with the lesson this weekend...

So I guess it's ok to ignore that message in the debugger?