Rotation methods deprecated, equivalent of 'didRotateFromInterfaceOrientation'?

Okay found it, just have to use the animateAlongsideTransition:completion: method on the passed UIViewControllerTransitionCoordinator.

- (void)viewWillTransitionToSize:(CGSize)size withTransitionCoordinator:(id<UIViewControllerTransitionCoordinator>)coordinator{       [coordinator animateAlongsideTransition:^(id<UIViewControllerTransitionCoordinatorContext> context)    {        UIInterfaceOrientation orientation = [[UIApplication sharedApplication] statusBarOrientation];        // do whatever    } completion:^(id<UIViewControllerTransitionCoordinatorContext> context)    {     }];    [super viewWillTransitionToSize:size withTransitionCoordinator:coordinator];}

The Swift Version of the answer by strange

override func viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) {    coordinator.animateAlongsideTransition({ (UIViewControllerTransitionCoordinatorContext) -> Void in        let orient = UIApplication.sharedApplication().statusBarOrientation        switch orient {        case .Portrait:            println("Portrait")            // Do something        default:            println("Anything But Portrait")            // Do something else        }        }, completion: { (UIViewControllerTransitionCoordinatorContext) -> Void in            println("rotation completed")    })    super.viewWillTransitionToSize(size, withTransitionCoordinator: coordinator)}

iOS 10.3 & Swift 3

override func willTransition(to newCollection: UITraitCollection, with coordinator: UIViewControllerTransitionCoordinator) {        coordinator.animate(alongsideTransition: { (_) in            let orient = newCollection.verticalSizeClass            switch orient {            case .compact:                print("Lanscape")///Excluding iPads!!!            default:                print("Portrait")            }        }, completion: { _ in            print("rotation completed")        })        super.willTransition(to: newCollection, with: coordinator)    }