iOS Xcode issue when swapping from Tab View Controller to swipe gestures

Question

I an app I was designing with a Tab View controller, which works fine.

I decided to change from a tab view controller to swipe gestures. However once done, whilst the swipe actions work fine, swapping between views with no issue, when I press a button on one of the screens (which works fine when working in tab view controllers) I get the following error:-

2013-12-23 20:07:57.702 TrialApp[3615:60b] * Assertion failure in -[CMStepCounter queryStepCountStartingFrom:to:toQueue:withHandler:], /SourceCache/CoreLocationFramework/CoreLocation-1613.5.2/Framework/CoreMotion/CMStepCounter.mm:211 2013-12-23 20:07:57.704 StepWise[3615:60b] Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid parameter not satisfying: start' ** First throw call stack: (0x1839c709c 0x18f945d78 0x1839c6f5c 0x1844f7194 0x1840b35a0 0x1000f039c 0x184541928 0x18398768c 0x1839872fc 0x183985024 0x1838c5b38 0x1892eb830 0x1869040e8 0x1000ef6ec 0x18ff2faa0) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)

Why would would this work fine when in a tab view controller, but fail when swipe actions are employed?

Answer 1

Thanks to rdelmar. Found that a variable was losing its data. Sorted as I now store this in NSUserDefaults.