Build Success BUT No Interface


Hey guys/gals, I successfully compiled the first project in the book but there is not gui, its just black. if i hit the square on the bottom of the phone emulator it takes me to installed apps and quiz is there but again, no gui when i run it. help please.

i found this error but have no idea where the issue is:

‘NSInvalidUnarchiveOperationException’, reason: ‘Could not instantiate class named NSLayoutConstraint’

thanks for the help


Post your code and we can take a look at it.



Also, when I get errors like the one you have I start putting in break points to see at what point the error is happening. This will clue you in to where your code is having issues.