-[UIViewController _keyboard]: unrecognized selector sent to instance 0x7b731ac0 - ios

Question

I am writing an app with 3 viewControllers contained inside of a MainViewController. One of these is controlled through the storyboard and shows ads. The other two viewControllers are displaying information. Depending on the menu button pressed and the viewController to be presented the app determines which viewController to change.
So far everything is working well except when ANY textField is selected. This causes the error to display. The instance is the viewController containing the textField, and is also the UIViewController named in the error. Also, the instance is not nil. I've placed a breakpoint at: textFieldShouldBeginEditing:
and this method is called before the crash happens. The app is universal and doesn't crash on the iPhone version, which uses the same setup except it only has the ads and another viewController displayed. Let me know if you need to see more code or have any ideas. I can't find the selector _keyboard anywhere and have no idea what to do from here.
I've tried to create a new project with minimal code to show the error, but new projects all work fine, so the problem isn't having too many viewControllers visible at once. I also know my transitioning code works fine because it works in the new projects. The viewControllers I've written are also not the problem, because the exact same viewController is used in the iPhone part of the app as well as in a new iPad only test project and the problem doesn't show up on them at all.
[edit - removed code, I tested the code in a new project and it worked fine]
[edit2 - added code and explanation]
#implementation FSMainiPadViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.leftView = [[UIView alloc] init];
self.rightView = [[UIView alloc] init];
if (!self.testVC) {
self.testVC = [[FSTestViewController alloc] initWithNibName:nil bundle:nil];
}
self.inputViewController = self.testVC;
self.resultsVC = [[FSResultsTableViewController alloc] initWithNibName:nil bundle:nil];
self.dataViewController = self.resultsVC;
self.leftView.frame = CGRectMake(0, VIEWFRAMEOFFSET/2, self.view.frame.size.width/2 , self.view.frame.size.height - IPADBANNERHEIGHT - VIEWFRAMEOFFSET/2 - MENUHEIGHT);
self.rightView.frame = CGRectMake((self.view.frame.size.width)/2, VIEWFRAMEOFFSET/2, self.view.frame.size.width/2, self.view.frame.size.height - IPADBANNERHEIGHT - VIEWFRAMEOFFSET/2 - MENUHEIGHT);
[self addChildViewController:self.inputViewController];
[self addChildViewController:self.dataViewController];
[self.view addSubview:self.inputViewController.view];
[self.view addSubview:self.dataViewController.view];
[self.dataViewController didMoveToParentViewController:self];
[self.inputViewController didMoveToParentViewController:self];
}
Selecting the textField causes this same error. I have literally commented out everything else in my MainViewController and it still causes this issue, but if I create a new project, even including my more complicated code and xib's, I can't recreate the crash.
Let me know if you want more code.
Stacktrace
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[FSSettingsViewController _keyboard]: unrecognized selector sent to instance 0x7da1dbf0'
*** First throw call stack:
(
0 CoreFoundation 0x0326d946 __exceptionPreprocess + 182
1 libobjc.A.dylib 0x02ef6a97 objc_exception_throw + 44
2 CoreFoundation 0x032755c5 -[NSObject(NSObject) doesNotRecognizeSelector:] + 277
3 CoreFoundation 0x031be3e7 ___forwarding___ + 1047
4 CoreFoundation 0x031bdfae _CF_forwarding_prep_0 + 14
5 UIKit 0x01e46d91 -[UIInputViewSet keyboard] + 52
6 UIKit 0x01b0807c -[UIKeyboardImpl setOrientation] + 94
7 UIKit 0x01b082c8 -[UIKeyboardImpl setFrame:] + 197
8 UIKit 0x01939084 UIViewCommonInitWithFrame + 1072
9 UIKit 0x01938bea -[UIView initWithFrame:] + 124
10 UIKit 0x01b02b62 -[UIKeyboardImpl initWithFrame:] + 107
11 UIKit 0x01b01c58 +[UIKeyboardImpl sharedInstance] + 158
12 UIKit 0x01e3bf4f -[UIPeripheralHost(UIKitInternal) _reloadInputViewsForResponder:] + 962
13 UIKit 0x01a845a5 -[UIResponder(UIResponderInputViewAdditions) reloadInputViews] + 316
14 UIKit 0x01a838ec -[UIResponder becomeFirstResponder] + 562
15 UIKit 0x0194a1c0 -[UIView(Hierarchy) becomeFirstResponder] + 114
16 UIKit 0x02115477 -[UITextField becomeFirstResponder] + 51
17 UIKit 0x01d183ef -[UITextInteractionAssistant(UITextInteractionAssistant_Internal) setFirstResponderIfNecessary] + 200
18 UIKit 0x01d1aa16 -[UITextInteractionAssistant(UITextInteractionAssistant_Internal) oneFingerTap:] + 2762
19 UIKit 0x01d0e287 _UIGestureRecognizerSendActions + 327
20 UIKit 0x01d0cb04 -[UIGestureRecognizer _updateGestureWithEvent:buttonEvent:] + 561
21 UIKit 0x01d0eb4d -[UIGestureRecognizer _delayedUpdateGesture] + 60
22 UIKit 0x01d124ca ___UIGestureRecognizerUpdate_block_invoke661 + 57
23 UIKit 0x01d1238d _UIGestureRecognizerRemoveObjectsFromArrayAndApplyBlocks + 317
24 UIKit 0x01d06296 _UIGestureRecognizerUpdate + 3720
25 UIKit 0x0191f26b -[UIWindow _sendGesturesForEvent:] + 1356
26 UIKit 0x019200cf -[UIWindow sendEvent:] + 769
27 UIKit 0x018e5549 -[UIApplication sendEvent:] + 242
28 UIKit 0x018f537e _UIApplicationHandleEventFromQueueEvent + 20690
29 UIKit 0x018c9b19 _UIApplicationHandleEventQueue + 2206
30 CoreFoundation 0x031911df __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 15
31 CoreFoundation 0x03186ced __CFRunLoopDoSources0 + 253
32 CoreFoundation 0x03186248 __CFRunLoopRun + 952
33 CoreFoundation 0x03185bcb CFRunLoopRunSpecific + 443
34 CoreFoundation 0x031859fb CFRunLoopRunInMode + 123
35 GraphicsServices 0x0519f24f GSEventRunModal + 192
36 GraphicsServices 0x0519f08c GSEventRun + 104
37 UIKit 0x018cd8b6 UIApplicationMain + 1526
38 FoodStorage 0x000a795d main + 141
39 libdyld.dylib 0x04e14ac9 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
This is the first time the Google machine has let me down. In all the problems I've had making this app, this is the only problem I can't seem to find anyone else having.

Answer 1

I'm going to assume this code works flawlessly when running on an iOS7 device and probably when compiled against the iOS7 SDK on an iOS8 device.
You appear to have had the misfortune of naming one of your properties the same thing as an Apple added property:
#interface UIResponder (UIResponderInputViewAdditions)
// Called and presented when object becomes first responder. Goes up the responder chain.
#property (nonatomic, readonly, retain) UIInputViewController *inputViewController NS_AVAILABLE_IOS(8_0);
#end
When the user taps on your text field, UIKit will grab your view controller thinking it's a UIInputViewController and send the private message _keyboard. Your view controller doesn't implement this method and it crashes the app.
The only thing you need to do here is rename your property from inputViewController to something else like myInputViewController.

Answer 2

The problem is in your iPad storyboard. Check all the view controllers' connections. You might have a connection in the storyboard that doesn't get use, delete them. It has got to be there if it works on iPhone and not the iPad. Place breakpoints everywhere to see the last position before crash.