Question

I have a very simple window based app, i am simply putting a navigation view controller as window’s root view controller and it’s crashing. This is the only thing i changed in the template project:

@interface AppDelegate : NSObject <UIApplicationDelegate> {
    UINavigationController *navigationController;
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    // Override point for customization after application launch.

    navigationController = [[UINavigationController alloc] init];


    [[self window] setRootViewController:navigationController];
    [self.window makeKeyAndVisible];
    return YES;
}

It crashes saying:

2011-05-26 20:18:57.194 ZebraSDKTest[5560:207] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<UICustomObject 0x8b3d760> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key navigationController.'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x00dbf5a9 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x00f13313 objc_exception_throw + 44
    2   CoreFoundation                      0x00dbf4e1 -[NSException raise] + 17
    3   Foundation                          0x00791677 _NSSetUsingKeyValueSetter + 135
    4   Foundation                          0x007915e5 -[NSObject(NSKeyValueCoding) setValue:forKey:] + 285
    5   UIKit                               0x0020d30c -[UIRuntimeOutletConnection connect] + 112
    6   CoreFoundation                      0x00d358cf -[NSArray makeObjectsPerformSelector:] + 239
    7   UIKit                               0x0020bd23 -[UINib instantiateWithOwner:options:] + 1041
    8   UIKit                               0x0020dab7 -[NSBundle(UINSBundleAdditions) loadNibNamed:owner:options:] + 168
    9   UIKit                               0x0001317a -[UIApplication _loadMainNibFile] + 172
    10  UIKit                               0x00013cf4 -[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 291
    11  UIKit                               0x0001e617 -[UIApplication handleEvent:withNewEvent:] + 1533
    12  UIKit                           

0x00016abf -[UIApplication sendEvent:] + 71
13  UIKit                               0x0001bf2e _UIApplicationHandleEvent + 7576
14  GraphicsServices                    0x00ff8992 PurpleEventCallback + 1550
15  CoreFoundation                      0x00da0944 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 52
16  CoreFoundation                      0x00d00cf7 __CFRunLoopDoSource1 + 215
17  CoreFoundation                      0x00cfdf83 __CFRunLoopRun + 979
18  CoreFoundation                      0x00cfd840 CFRunLoopRunSpecific + 208
19  CoreFoundation                      0x00cfd761 CFRunLoopRunInMode + 97
20  UIKit                               0x000137d2 -[UIApplication _run] + 623
21  UIKit                               0x0001fc93 UIApplicationMain + 1160
22  ZebraSDKTest                        0x00002549 main + 121
23  ZebraSDKTest                        0x000024c5 start + 53

)

Answer 1

Looks like you have a connection to a former existing UINavigationController IBOutlet in one of your nib files.

Start with MainWindow.xib and check for such a connection.