问题
* Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: '* -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (NSLayoutConstraint)'
I have a very simple app
One view has one button
I Control Click and dragged the button to a second view and selected MODAL
When I run it in the simulator, everything works
When i run it in my iPad running iOS 5.1.1, it crashes with the error above. I have no idea why and there is no code.
回答1:
This is occuring because you are using Xcode 4.5 (or previously the beta) which uses "auto layout" by default. Auto layout is only available on iOS 6 so you will get a runtime error on previous iOS versions.
You can fix this by opening your Storyboard, opening the Utilities pane, and disabling the "Use Autolayout" checkbox in the first tab/section:
For regular non-storyboard nibs, select the top-level view to access this option.
回答2:
In Your Xib-> Identity and type ->Interface Builder Document -> uncheck useAutoLayout check box,this is the new feature with Ios6
来源：https://stackoverflow.com/questions/11085859/how-can-i-fix-nsinvalidunarchiveoperationexception