iOS Can You Tell Me Why This Works

[zachsilvey]

In *AppDelegate.h I create a UINavigation Controller and make it a property

UINavigationController *navigationController;
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;

then in *AppDelegate.m I use

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    
	RootViewController *rootViewController = [[RootViewController alloc]initWithNibName:@"RootViewController" bundle:nil];
	navigationController = [[UINavigationController alloc]initWithRootViewController:rootViewController];

	[self.window addSubview:navigationController.view];
	
	[rootViewController release];
	
    [self.window makeKeyAndVisible];
    
    return YES;
}

Why is it in the RootViewController.m I can call this?

[self.navigationController pushViewController:secondLevelViewController animated:YES];

navigationController doesn't belong to that class so why is it that I can call "self.navigationController"?

 

[robbieduncan]

Because all view controllers have a navigationController property (it's in the documentation). When you add a view controller to a navigation controller (either by pushing it or initing the navigation controller with a root view controller) it get's set by the navigation controller.

 

[zachsilvey]

So it was just by chance that I named the UINavigationController "navigationController'?

I should spend more time in the documentation.

 

[robbieduncan]

So it was just by chance that I named the UINavigationController "navigationController'?

I should spend more time in the documentation.

Yes. That had absolutely no impact on it.