How to force a UIViewController to Portrait orientation in iOS 6

If you want all of our navigation controllers to respect the top view controller you can use a category so you don't have to go through and change a bunch of class names.

@implementation UINavigationController (Rotation_IOS6)

-(BOOL)shouldAutorotate
{
    return [[self.viewControllers lastObject] shouldAutorotate];
}

-(NSUInteger)supportedInterfaceOrientations
{
    return [[self.viewControllers lastObject] supportedInterfaceOrientations];
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
    return [[self.viewControllers lastObject] preferredInterfaceOrientationForPresentation];
}

@end

As a few of the comments point to, this is a quick fix to the problem. A better solution is subclass UINavigationController and put these methods there. A subclass also helps for supporting 6 and 7.

The best way for iOS6 specifically is noted in "iOS6 By Tutorials" by the Ray Wenderlich team - http://www.raywenderlich.com/ and is better than subclassing UINavigationController for most cases.

I'm using iOS6 with a storyboard that includes a UINavigationController set as the initial view controller.

//AppDelegate.m - this method is not available pre-iOS6 unfortunately

- (NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window{
NSUInteger orientations = UIInterfaceOrientationMaskAllButUpsideDown;

if(self.window.rootViewController){
    UIViewController *presentedViewController = [[(UINavigationController *)self.window.rootViewController viewControllers] lastObject];
    orientations = [presentedViewController supportedInterfaceOrientations];
}

return orientations;
}

//MyViewController.m - return whatever orientations you want to support for each UIViewController

- (NSUInteger)supportedInterfaceOrientations{
    return UIInterfaceOrientationMaskPortrait;
}