scaledValueForValue: called on a font that doesn't have a text style set

Question

I am currently using the Xcode 6 pre release (not beta) and the simulator on OS X 10.10 Yosemite beta 7. I am trying to build a project developed in xcode 6, but the app crashes whenever I open a certain view controller. This view controller literally has no code in it (it is an empty, static, table view controller that has a couple of default cells and labels).

The error given is:

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason:   'scaledValueForValue: called on a font that doesn't have a text style set' 

And right before I am given this assertion failure:

*** Assertion failure in -[UICTFont _scaledValueForValue:],          /SourceCache/UIFoundation_Sim/UIFoundation-371/UIFoundation/iOS/UIFont.m:496 

I seriously have no idea what is going on, I tried setting breakpoints in the VC but the error happens after the viewDidLoad method is called (and thus after all my code is executed).

Any Ideas? The fonts for everything in my project is 'Baskerville' and I have tried changing that but it does not affect the crash.

Oh, and it works fine if I use Xcode 5.

Update 9/24: So I am still unable to figure this out. I tried using the fontWithDescriptor method, but it still crashes. The funny thing is, I have plenty of pages that use custom fonts and most of them work fine, but there are two VCs that crash immediately when I go to them... one of them doesn't even have any custom fonts. I really appreciate all of your feedback, but does anyone have any other ideas/fixes? I am using the official release of Xcode and it still doesn't work.

Answer 1

This problem has been fixed in iOS 8.1.

Instead of spending time building a custom header/footer view, I just not apply the custom font to devices running iOS 8.0. Most people will probably have updated to iOS 8.1 anyway.

I use the following code for this:

NSOperatingSystemVersion iOS_8_1 = (NSOperatingSystemVersion){8, 1, 0};  if (![[NSProcessInfo processInfo] respondsToSelector:@selector(isOperatingSystemAtLeastVersion:)]     || [[NSProcessInfo processInfo] isOperatingSystemAtLeastVersion:iOS_8_1]) {     header.textLabel.font = [UIFont fontWithName:@"Avenir-Medium" size:header.textLabel.font.pointSize]; } 

The first statement is true if the device is running an iOS version lower than 8 (since isOperatingSystemAtLeastVersion: was introduced in iOS 8.0). The second statement is true if the device if running iOS 8.1 or later. With both statements we thus only exclude devices running iOS 8.0.

Answer 2

Okay I finally figured it out.

This occurs when grouped table views have section headers and possibly footers. As a temporary workaround I am just removing the headers/footers from the grouped tableviews, but if you really need the font you can create a custom header view by overriding the "viewForHeaderInSection", and setting the font on your custom view's label.

Still, this is definitely a bug in iOS 8 and hopefully it will be fixed soon.