“interfaceOrientation” is deprecated in iOS 8, How to change this method Objective C

Getting the device orientation is not correct. For instance, the device might be in landscape mode, but a view controller that only supports portrait will remain in portrait.

Instead, use this:

[[UIApplication sharedApplication] statusBarOrientation]

Another bonus is that it still uses the UIInterfaceOrientation enum, so very little of your code needs to change.