ViewWillAppear is never called automatically I have to call them manually. ViewWillDisappear is often called though.
I do not know where to debug this.
I suppose the problem is because I created the application on 4.1 where people have to call viewWillAppear explicitly.
I suppose, because viewWillAppear will be called depending on its relation with window I can check if my viewController has an outlet to window.
How do I do so?
I suspected the problem is somewhere in my delegate:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[Crashlytics startWithAPIKey:#"a08863b514ef09558ba82fec070cc7468fdbeeae"];
if(getenv("NSZombieEnabled") || getenv("NSAutoreleaseFreedObjectCheckEnabled"))
{
NSLog(#"NSZombieEnabled/NSAutoreleaseFreedObjectCheckEnabled enabled!");
}
[self.window addSubview:self.navController.view]; //This seem to be the problem. I should have specified the viewController and not the view
[self.navController pushViewController:self.MainBadgerApplication animated:YES];
//[cachedProperties singleton].lastAnchor =[cachedProperties currentLocation];
[cachedProperties singleton].currentAnchor=[cachedProperties currentLocation];
self.MainBadgerApplication.selectedIndex=0;
[BNUtilitiesQuick tabBarController:self.MainBadgerApplication didSelectViewController:self.MainBadgerApplication.selectedViewController];
[self.window makeKeyAndVisible];
return YES;
}
I suspected that
[self.window addSubview:self.navController.view]; is the issue.
Also I've heard before ios5 you do have to call viewController explicitly. So should I create a different program for ios5 and ios4 (not like there is any danger in calling viewController twice for my program)
I suspected that [self.window addSubview:self.navController.view]; is the issue.
Probably. You should be doing this instead:
self.window.rootViewController = self.navController;
Just adding the view doesn't put your view controller into the hierarchy properly. See the WWDC 2011 view controller containment video for more information.
In my app delegate, I have:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.viewController = [[CGMContainerViewController alloc] init];
self.window.rootViewController = self.viewController;
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
I have an unmodified CGMContainerViewController.h/m and a modified CGMContainerViewController.xib (added a button). The view is linked to the File Owner.
Why is the view from the XIB not showing?
EDIT: Is it because I'm trying to load a view with a status bar into the window?
From the looks of your code, you aren't loading any XIB files. You need to call initWithNibName:
self.viewController = [[CGMContainerViewController alloc] initWithNibName:
#"CGMContainerViewController" bundle: nil];
Make sure that your File's Owner in the XIB is set to CGMContainerViewController
Okay. I think it was because for a UINavigationController, you have to set the rootViewController and all the layers. I just changed it to a UIViewController because I didn't really need the navigation, just the navigation bar.
The problem which I faced is .If you name your viewController with special character with "-" and some other things your xib will not get loaded
example--> (wrong naming)
view-controller1 (If naming is like this then the xib wont get loaded)
example--->(correct naming)
viewController1 (xib will get loaded)
I am new and am working on an exercise which involves starting with a navigation-based template. Since I am running Xcode 4.2 which no longer has that template, I have started with an empty application template, and then copied the directory structure of the completed app.
Since the empty app template starts only with an AppDelegate.h, .m files, I started adding other required files, including the MainWindow.xib, and the RootViewController.h, .m files. Did some tweaking of the #import directive so that it could see the right files, and could start alright.
However, when I try to run it on the iOS Simulator, I got this message: Applications are expected to have a root view controller at the end of application launch
Terminating in response to SpringBoard's termination.
Program ended with exit code: 0
What additional changes do I need to make so that the app can see the RootViewController?
Thank you.
In -[AppDelegate application:didFinishLaunchingWithOptions:], you need to set your window's rootViewController property.
You need to set the rootViewController property of AppDelegate's _window:
- (BOOL)application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
_window.rootViewController = self.myNavigationController;
[_window makeKeyAndVisible];
return YES;
}
To start a traditional navigation-based project in XCode 4.2, I find it easier to start with the single-view template. Then, in AppDelegate, I substitute the generated UIViewController with a UINavigationController.
self.window.rootViewController=self.yourviewControollerobj
You can set like this. First set the window bounds then add you navigation controller with root view controller.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.window = [[UIWindow alloc]initWithFrame:[[UIScreen mainScreen]bounds]];
MainViewController *vc = [MainViewController new];
/*
* If you are using .xib you should create UIViewontroller like this
* MainViewController *vc = [MainViewController alloc] initWithNibName:#"MainViewController" bundle:nil]
*/
UINavigationController *nc = [[UINavigationController alloc] initWithRootViewController:vc];
[self.window setRootViewController:self.nc];
[self.window makeKeyAndVisible];
return YES;
}
MyViewController *rootCtr = [[MyViewController alloc] init];
[rootCtr.view addSubview:myView];
window.rootViewController = rootCtr;
I am getting a message within the console when I run my app that says:
2011-11-16 19:17:41.292 Juice[8674:707] Applications are expected to have a root view controller at the end of application launch
I have heard from others that this has to do with the method didFinishLaunchingWithOptions
If anyone has any suggestions for why I am getting this error, it would be much appreciated.
My code for the method:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
[window addSubview:tabBarController.view];
[window makeKeyAndVisible];
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];
return YES;
}
You should replace the
[window addSubview:tabBarController.view];
to
[self.window setRootViewController:tabBarController];
Maybe you built your project with 'Empty Application' and forgot to set the rootViewController in your didFinishLaunchingWithOptions (which exists in your AppDelegate.m).
However, if you build your project with 'Single View Application' or some other type, the project will set the rootViewController via xib by default (which might be a MainWindow.xib in your project).
I had the same problem on iOS 5, after adding a storyboard to an "empty" project. It turns out I had to remove all the lines in AppDelegate.m that set values to self.window.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
//self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
//self.window.backgroundColor = [UIColor whiteColor];
//[self.window makeKeyAndVisible];
return YES;
}
If you have MainWindow.xib, make sure you set Main Interface in Target's summary to MainWindow.
The way I got this error Applications are expected to have a root view controller at the end of application launch to disappear, was to ensure the loadView method in my root view controller was calling [super loadView]. Hope this helps someone.
Try using self.window instead of window (if your setup has window being synthesized with something like #synthesize window=_window;):
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Override point for customization after application launch.
[self.window addSubview:tabBarController.view];
[self.window makeKeyAndVisible];
[[UIApplication sharedApplication] setStatusBarHidden:NO withAnimation:UIStatusBarAnimationFade];
return YES;
}
2nd possibility:
In your main.m make sure the last argument is the name of the App Delegate. In your case, it looks like it should be:
retVal = UIApplicationMain(argc, argv, nil, #"JuiceAppDelegate");
Solution:
As #marcus13 said in the comments below.. This was fixed was found in this SO answer: Applications are expected to have a root view controller at the end of application launch - by by moving the UIAlertView methods from -(void)viewDidLoad to -(void)viewDidAppear:(BOOL)animated
Another cause:
I was in IB attaching File Owner to a new small ImageView I'd dragged onto the View. I hadn't called it an IBOutlet in the .h file, so when I ctrl-dragged to it, the new Imageview wasn't listed as a possible connection. The only possibility displayed in the little black box was View. I must have clicked, inadvertently. I made a few changes then ran the program and got the Root Controller error. The fix was reconnecting File Owner to the bottom View in the xib - IB screen.
I just ran into this issue while building a new project from scratch. I added a StoryBoard and build my whole interface, but i did not select a template.
When doing it this way, you have to make sure of 3 main things:
Always select your initial controller (TabBarcontroller or NavigationController) as the initial view in your Storyboard.
Change the code in your Appdelegate.m from this
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
[self.window makeKeyAndVisible];
return YES;
}
to this
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
return YES;
}
Check your [ProjectName]-Info.plist file. If there is no key named "Main storyboard file base name", you have to manually add it and set it's value to the name of your storyboard file (without the extension).
After i did all of these steps, my application ran perfectly.
I also had the same problem. All I got was a black screen. Turns out I had inadvertently removed:
[self.window makeKeyAndVisible];
from my code. Hope this helps someone!
I had two outlets assigned to "view" in the storyboard's root view controller. Right-click on "view controller" and make sure there's only one "view".
I also had the same error while developing an app that uses sqlite Database.
I was showing alertView when the db file transfer failed.
This was a mistake since you cannot show any popovers/alertview/actions without any rootViewController set!
I fixed it by ensuring that any function that creates and shows these alerts/popovers/actionsheets are called after
self.window.rootViewController = self.tabBarController;
[self.window makeKeyAndVisible];
[someObject functionthatDisplayAlerts];
I know this post is old but I ran into this today.
It's because I created a UIAlertView in didFinishLaunchingWithOptions.
Assuming then we should not be doing this because I commented it out and the error went away. I removed my comments and the error came back.
The app doesn't crash, I just get that logged error.
I had the same problem with my App. It appeared when I added another view controller to my project and tried to set it as the root view controller in AppDelegate. I tried several solutions, but none of them could fix the problem. Finally I found the cause: I had two localized versions of the MainWindow.xib file (One for german and another for english localization). So I deleted the english file and reconnected the IBOutlets in MainView.xib. This solved the problem.
I'm not sure if this will help anybody else, but if you have used interface builder to create your mainWindow and have done all the linking between the delegate make sure you don't have the following code within application:didFinishLaunching ...
[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]
I was having the same error until I removed the above line. Hope that helps!
EDIT: Doing the above now has my viewControllers viewDidAppear method being called twice ?
If you are using Storyboard, but created an empty project, you probably forgot to set the Main storyboard to your *.storyboard file in the Summary tab in your project settings. It helped me to solve this problem.
If you are starting from an empty you have to make this addition to your AppDelegate.m file, to "point" the window to the rootViewController (self.window.rootViewController = [[[ViewControllerName alloc] initWithNibName:#"ViewControllerName" bundle:nil] autorelease];)
Like so:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
self.window.rootViewController = [[[ViewControllerName alloc] initWithNibName:#"ViewControllerName" bundle:nil] autorelease];
[self.window makeKeyAndVisible];
return YES;
}
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