iOS Swift 키보드 show/hide 처리

    override func viewWillAppear(animated: Bool) {

        super.viewWillAppear(animated)

        

        registerForKeyboardNotifications()

    }

    

    override func viewWillDisappear(animated: Bool) {

        super.viewWillDisappear(animated)

        

        unregisterForKeyboardNotifications()

    }

    //MARK: Keyboard events

    func registerForKeyboardNotifications() {

        NSNotificationCenter.defaultCenter().addObserver(self, selector:#selector(keyboardWillShow), name: UIKeyboardWillShowNotification, object: nil)

        NSNotificationCenter.defaultCenter().addObserver(self, selector:#selector(keyboardWillHide), name: UIKeyboardWillHideNotification, object: nil)

    }

    func unregisterForKeyboardNotifications() {

        NSNotificationCenter.defaultCenter().removeObserver(self, name:UIKeyboardWillShowNotification, object: nil)

        NSNotificationCenter.defaultCenter().removeObserver(self, name:UIKeyboardWillHideNotification, object: nil)

    }

    

    func keyboardWillShow(note: NSNotification) {

        // UI를 키보드 위로 올려준다

        print("keyboardWillShow")

        let s = note.userInfo![UIKeyboardFrameEndUserInfoKey]

        let rect = s!.CGRectValue()

        

        // 입력창 위치를 올려줌

        var frame = textField.frame

        frame.origin.y -= rect.height

        textField.frame = frame

        let keyboardFrameEnd = view!.convertRect(rect, toView: nil)

        view.frame = CGRectMake(0, 0, keyboardFrameEnd.size.width, keyboardFrameEnd.origin.y)

        view.layoutIfNeeded()

    }

    

    func keyboardWillHide(note: NSNotification) {

        // UI를 원위치 한다

        print("keyboardWillHide")

        let s = note.userInfo![UIKeyboardFrameBeginUserInfoKey]

        let rect = s!.CGRectValue()

        var frame = textField.frame

        frame.origin.y += rect.height

        textField.frame = frame

        

        frame = view.frame

        view.frame = CGRectMake(frame.origin.x, frame.origin.y, frame.width, frame.height+ rect.height)

        view.layoutIfNeeded()

    }