Keyboard covers text fields at the bottom of my view

I have searched

here: Move a view up only when the keyboard covers an input field

here: Move textfield when keyboard appears swift

here: How to make a UITextField move up when keyboard is present?

and here: https://developer.apple.com/library/content/documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/KeyboardManagement/KeyboardManagement.html

Unfortunately, all of the links and seemingly everywhere else I can find do not give a good clean solution that I am looking for. They are either outdated with Obj-c code, or plain do not work in the current iteration of Xcode 9 with Swift 4.

How do I manage a keyboard that is covering text fields at the bottom of my view? I want the screen's view to move only when they keyboard is covering the text field view, without using a scroll view, with the ability to animate this to make it look pretty rather than have it just snap, and most importantly I do not want to use an outside library.

CoreAnimation libraries from Apple are great and all, but all of the sample code is outdated and in objective c which is deprecated at this point (I cannot believe that Apple isn't updating their documentation).

If someone could point me in the right direction to updated and current code or a library from Apple I am missing that will specifically address this issue, it would be much appreciated.

Solution

This code will work, making your textField animating to above keyboard if its frame intersects with that of keyboard and animating back to original position on keyboard hide.

@IBOutlet weak var textField: UITextField!

  var offsetY:CGFloat = 0

  override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    NotificationCenter.default.addObserver(self, selector: #selector(ViewController.keyboardFrameChangeNotification(notification:)), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
  }

  func keyboardFrameChangeNotification(notification: Notification) {
    if let userInfo = notification.userInfo {
      let endFrame = userInfo[UIKeyboardFrameEndUserInfoKey] as? CGRect
      let animationDuration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as? Double ?? 0
      let animationCurveRawValue = (userInfo[UIKeyboardAnimationCurveUserInfoKey] as? Int) ?? Int(UIViewAnimationOptions.curveEaseInOut.rawValue)
      let animationCurve = UIViewAnimationOptions(rawValue: UInt(animationCurveRawValue))
      if let _ = endFrame, endFrame!.intersects(self.textField.frame) {
        self.offsetY = self.textField.frame.maxY - endFrame!.minY
        UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
          self.textField.frame.origin.y = self.textField.frame.origin.y - self.offsetY
        }, completion: nil)
      } else {
        if self.offsetY != 0 {
          UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
            self.textField.frame.origin.y = self.textField.frame.origin.y + self.offsetY
            self.offsetY = 0
          }, completion: nil)
        }
      }
    }
  }