How to lock orientation of one view controller to portrait mode only in Swift

Question

Since my app got support for all orientation. I would like to lock only portrait mode to specific UIViewController.

e.g. assume it was Tabbed Application and when Si

Answer 1

This is a generic solution for your problem and others related.

1. Create auxiliar class UIHelper and put on the following methods:

    /**This method returns top view controller in application  */
    class func topViewController() -> UIViewController?
    {
        let helper = UIHelper()
        return helper.topViewControllerWithRootViewController(rootViewController: UIApplication.shared.keyWindow?.rootViewController)
    }

    /**This is a recursive method to select the top View Controller in a app, either with TabBarController or not */
    private func topViewControllerWithRootViewController(rootViewController:UIViewController?) -> UIViewController?
    {
        if(rootViewController != nil)
        {
            // UITabBarController
            if let tabBarController = rootViewController as? UITabBarController,
                let selectedViewController = tabBarController.selectedViewController {
                return self.topViewControllerWithRootViewController(rootViewController: selectedViewController)
            }

            // UINavigationController
            if let navigationController = rootViewController as? UINavigationController ,let visibleViewController = navigationController.visibleViewController {
                return self.topViewControllerWithRootViewController(rootViewController: visibleViewController)
            }

            if ((rootViewController!.presentedViewController) != nil) {
                let presentedViewController = rootViewController!.presentedViewController;
                return self.topViewControllerWithRootViewController(rootViewController: presentedViewController!);
            }else
            {
                return rootViewController
            }
        }

        return nil
    }

2. Create a Protocol with your desire behavior, for your specific case will be portrait.

protocol orientationIsOnlyPortrait {}

Nota: If you want, add it in the top of UIHelper Class.

3. Extend your View Controller

In your case:

class Any_ViewController: UIViewController,orientationIsOnlyPortrait {

   ....

}

4. In app delegate class add this method:

 func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
        let presentedViewController = UIHelper.topViewController()
        if presentedViewController is orientationIsOnlyPortrait {
            return .portrait
        }
        return .all
    }

Final Notes:

• If you that more class are in portrait mode, just extend that protocol.
• If you want others behaviors from view controllers, create other protocols and follow the same structure.
• This example solves the problem with orientations changes after push view controllers