The validated answer doesn't take in account the textfield position and has some bug (double displacement, never come back the primary position, displacement even if the texfield is on top of the view...)
The idea is :
then we will be able to move the view only if necessary and of the specific displacement in oder to have the focused texField just over the keyboard
Here is the code :
Swift 4
class ViewController: UIViewController, UITextFieldDelegate {
var textFieldRealYPosition: CGFloat = 0.0
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(VehiculeViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(VehiculeViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
// Delegate all textfields
}
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
let distanceBetweenTextfielAndKeyboard = self.view.frame.height - textFieldRealYPosition - keyboardSize.height
if distanceBetweenTextfielAndKeyboard < 0 {
UIView.animate(withDuration: 0.4) {
self.view.transform = CGAffineTransform(translationX: 0.0, y: distanceBetweenTextfielAndKeyboard)
}
}
}
}
@objc func keyboardWillHide(notification: NSNotification) {
UIView.animate(withDuration: 0.4) {
self.view.transform = .identity
}
}
func textFieldDidBeginEditing(_ textField: UITextField) {
textFieldRealYPosition = textField.frame.origin.y + textField.frame.height
//take in account all superviews from textfield and potential contentOffset if you are using tableview to calculate the real position
}
}