handling keyboard Notifications with swift 3.swift

keyboard.swift

  override function viewDidLoad() {
    ...
    
     
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChangeFrame), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
        
    ...
}
  
  func keyboardWillShow(_ notification:Notification) {
        adjustingHeight(true, notification: notification)
    }
    
    func keyboardWillHide(_ notification:Notification) {
        adjustingHeight(false, notification: notification)
    }
    
    func keyboardWillChangeFrame(_ notification: Notification) {
        adjustingHeight(false, notification: notification)
    }
    
    func adjustingHeight(_ show:Bool, notification:Notification) {
        
        var userInfo = (notification as NSNotification).userInfo!
        let keyboardFrame:CGRect = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let animationDurarion = userInfo[UIKeyboardAnimationDurationUserInfoKey] as! TimeInterval
        let changeInHeight = (keyboardFrame.height ) * (show ? 1 : 0)
        self.bottomSpace.constant = changeInHeight

        UIView.animate(withDuration: animationDurarion, animations: { () -> Void in
            self.view.layoutIfNeeded()
        })
    }
    

Great Example!!