Adjust the view size based on whether the keyboard is open or closed. Sizes dynamically based on keyboard.

AdjustViewSizeBasedOnKeyboard.swift

override func viewDidLoad() {
        super.viewDidLoad()
       
        // Listen for keyboard changes
        NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }
    
    func keyboardWillShow(sender: NSNotification) {
        if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            let keyboardHeight = keyboardSize.height
            self.view.frame.origin.y -= keyboardHeight
        }
    }
    
    func keyboardWillHide(sender: NSNotification) {
        if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
            let keyboardHeight = keyboardSize.height
            self.view.frame.origin.y += keyboardHeight
        }
    }