pushing nil rootViewController onto target <UINavigationController
I've been researching this all day but I haven't found anything about the rootViewController in relation to this error message. I know what the problem is but have no idea how to fix it. My problem is that my window.rootViewController is not connected or shows null and I can't figure out what to do. I've tried everything I could think of in code and in IB, but bad things happen whenever I change something. This is the message I get: "Application tried to push a nil view controller on target UINavigationController"
I can see the window.rootViewController from an NSLog statement: "window.rootViewController : (null)"
of course, everything was working perfectly before upgrading my Xcode to 4.2 and ios5. :)
btw - the view loads but I cannot work any of the buttons, they do not light up at all. And my navigation works fine too.
here is my appDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[DDLog addLogger:[DDTTYLogger sharedInstance]];
NSLog(@"Viewcontroller : %@", self.viewController);
// Set the view controller as the window's root view controller and display.
//self.window.rootViewController = self.viewController;
//do it this way, previous version not supported in ios5 - may need to check version for compatibility
[self.window addSubview:self.viewController.view];
//set up navigation controller
NSLog(@"window.rootViewController : %@", self.window.rootViewController);
navigationController = [[UINavigationController alloc]
initWithRootViewController:self.window.rootViewController];
navigationController.navigationBarHidden = YES;
NSLog(@"navigationController : %@", navigationController);
[window addSubview:navigationController.view];
[window makeKeyAndVisible];
//force this view to be landscape
[application setStatusBarOrientation: UIInterfaceOrientationLandscapeRight animated:NO];
[self.navigationController.view setTransform: CGAffineTransformMakeRotation(M_PI / 2)];
[self.navigationController.view setFrame:CGRectMake(0, 0, 748, 1024)];
[UIView commitAnimations];
return YES;
}
Thank you.
According to the docs:
Discussion The root view controller provides the content view of the window. Assigning a view controller to this property (either programmatically or using Interface Builder) installs the view controller's view as the content view of the window. If the window has an existing view hierarchy, the old views are removed before the new ones are installed.
Double check your nib file to make sure it is connect.
Although the "Application tried to push a nil view controller on target UINavigationController" sounds like you maybe losing your VC reference. How is the property set for this? Is it retained?
Here are the docs.
http://developer.apple.com/library/ios/documentation/uikit/reference/UIWindow_Class/UIWindowClassReference/UIWindowClassReference.html#//apple_ref/doc/uid/TP40006817-CH3-SW33
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