Button position must change depending On Keyboard with swift

button.bk_defaultButtonHeight = 50  // example size.

button.bk_onKeyboard(keyboardHeight: height)
or
button.bk_onKeyboard(scrollView: scrollView, keyboardHeight: height)

override func viewDidLoad() {
    super.viewDidLoad()
    
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_:)), name: UIResponder.keyboardWillShowNotification, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
    
    button.bk_defaultButtonHeight = buttonHeightConstraint.constant  // Stores the default size of the button.
}

@objc func keyboardWillShow(_ notification: Notification) {
    var visibleHeight: CGFloat = 0
     
    if let userInfo = notification.userInfo {
        if let windowFrame = UIApplication.shared.keyWindow?.frame,
            let keyboardRect = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
            visibleHeight = windowFrame.intersection(keyboardRect).height
        }
    }
    
    updateButtonLayout(height: visibleHeight)
}
 
@objc func keyboardWillHide(_ notification: Notification) {
    updateButtonLayout(height: 0)
}

func updateButtonLayout(height: CGFloat) {
    button.bk_onKeyboard(scrollView: scrollView, keyboardHeight: height)
}

pod 'ButtonOnKeyboard'