Question

Consider the following app delegate entry point:

- (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];

    // Custom view controller
    main = [[MainView alloc] initWithNibName:@"MainView" bundle:nil];
    [self.window addSubview:main.view];

    return YES;
}

Everything is Apple stock code, except the “custom view controller” part. There, a custom view controller is grabbed, and effectively added as the main view of the app.

Problem: the widgets in the view are 20px above where they should be. In other words, top 20px of the view’s contents are obscured by the status bar.

But: after rotation, the view and its contents are positioned correctly, and the status bar overlap no longer appears.

What’s going on here? And specifically, what’s the pattern/best practice to make sure that things are positioned correctly also when adding the subview to the window initially?

Answer 1

You are using the wrong method for initializing your UIWindow’s frame. Yous should be using [[UIScreen mainScreen] applicationFrame] for exactly the reason you are talking about. Read this for more (basically applicationFrame takes care of the status bar issue).