Handling Notifications in Swift

SwiftNotifications.swift

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
                            
    var window: UIWindow!

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        window = UIWindow(frame: UIScreen.mainScreen().bounds)

        let dev = UIDevice.currentDevice()
        dev.beginGeneratingDeviceOrientationNotifications()

        //Handled by selector
        let nc = NSNotificationCenter.defaultCenter()
        nc.addObserver(self, selector: "orientationChanged:", name: UIDeviceOrientationDidChangeNotification, object: dev)

        //using an inline closure
        nc.addObserverForName(UIDeviceOrientationDidChangeNotification, object: dev, queue: NSOperationQueue.mainQueue(), usingBlock: {
            note in if let object: UIDevice = note.object? as? UIDevice {
                println("orientationChangedInlineBlock: \(object.orientation.toRaw())")
            }})

        //using a named closure
        nc.addObserverForName(UIDeviceOrientationDidChangeNotification, object: dev, queue: NSOperationQueue.currentQueue(), usingBlock: orientationBlock)

        window.backgroundColor = UIColor.whiteColor()
        window.makeKeyAndVisible()
        return true
    }

    let orientationBlock = { (note: NSNotification!) -> () in
        if let deviceNotification = note.object? as? UIDevice {
            println("orientationBlock \(deviceNotification.orientation.toRaw())")
        }
    }

    func orientationChanged(note: NSNotification) -> () {
        if let object: UIDevice = note.object? as? UIDevice {
            println("orientationChanged: \(object.orientation.toRaw())")
        }
    }