Rotation.swift

import Foundation
import UIKit

extension UINavigationController {

    public override func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {

        if let visibleViewController = visibleViewController {
            return visibleViewController.supportedInterfaceOrientations()
        } else if let topViewController = topViewController {
            return topViewController.supportedInterfaceOrientations()
        } else {
            return .Portrait
        }
    }

    public override func shouldAutorotate() -> Bool {
        if let visibleViewController = visibleViewController {
            return visibleViewController.shouldAutorotate()
        } else if let topViewController = topViewController {
            return topViewController.shouldAutorotate()
        } else {
            return false
        }
    }

    override public func preferredInterfaceOrientationForPresentation() -> UIInterfaceOrientation {
        if let visibleViewController = visibleViewController {
            return visibleViewController.preferredInterfaceOrientationForPresentation()
        } else if let topViewController = topViewController {
            return topViewController.preferredInterfaceOrientationForPresentation()
        } else {
            return .Portrait
        }
    }
}

extension UIViewController {

    public override func supportedInterfaceOrientations() -> UIInterfaceOrientationMask {
        return .Portrait
    }

    public override func shouldAutorotate() -> Bool {
        return false
    }

    override public func preferredInterfaceOrientationForPresentation() -> UIInterfaceOrientation {
        return .Portrait
    }
}