Confusion with UINavigationControllers in SplitViewController

Question

I am setting up an iPad app that uses a SplitViewController. In my app delegate I have the following in didFinishLaunchingWithOptions:

UISplitViewController *splitViewController = (UISplitViewController *)self.window.rootViewController;
UINavigationController *leftNavController = [splitViewController.viewControllers objectAtIndex:0];
LeftViewController *leftViewController = (LeftViewController*)[leftNavController topViewController];
DetailViewController *detailViewController = [splitViewController.viewControllers objectAtIndex:1];
NSLog(@"Detail View Ctrl >> %@", [detailViewController class]);

When I run the app, the NSLog statement returns "UINavigationController" when DetailViewController is actually a subclass of UIViewController. However, in XCode, code completion shows all the methods that are implemented in the DetailViewController subclass. Any ideas? Thanks!

Answer 1

I think your DetailViewController is actually embedded inside a UINavigationController, and your fourth line is in error. Take a look instead at the topViewController for the second view controller inside your split view controller, much like you do for the LeftViewController.

The reason Xcode is continuing to suggest completion for DetailViewController methods is because you've given it that type. Code completion doesn't rely on runtime behavior (how could it?) – instead, it relies on static analysis of the code that you type. If you tell Xcode that something is a DetailViewController, it'll believe you and autocomplete based on that information.