Get Keyboard Toolbar Height - swift

Question

i have the same question as this :
iPhone Keyboard with accessory view height problems
but the answer has no new solution and does not solve anything!

Answer 1

I found a good solution Here
Made few changes and updated it to swift 4.2.
Few points to be mentioned
Created an outlet of textfield and bottom constraint from Storyboard to ViewController
Bottom constraint is used for moving the textfield up and down.
class ViewController: UIViewController {
#IBOutlet weak var inputField: UITextField!
#IBOutlet weak var textFieldBottomContraint: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
self.setUpKeyBoardNotifications()
self.addToolBarTo(uiElement: self.inputField)
}
func setUpKeyBoardNotifications()
{
NotificationCenter.default.addObserver(self,
selector: #selector(self.keyboardNotification(notification:)),
name: UIResponder.keyboardWillChangeFrameNotification,
object: nil)
}
func addToolBarTo(uiElement element:UITextField)
{
let numberToolbar = UIToolbar(frame:CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 45))
numberToolbar.barStyle = .black
numberToolbar.items = [
UIBarButtonItem(title: "Cancel", style: .plain, target: self, action: #selector(ViewController.cancelAction)),
UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil),
UIBarButtonItem(title: "Done", style: .plain, target: self, action: #selector(ViewController.doneAction))]
numberToolbar.sizeToFit()
element.inputAccessoryView = numberToolbar
}
#objc func keyboardNotification(notification: NSNotification) {
if let userInfo = notification.userInfo {
let endFrame = (userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue
let endFrameY = endFrame?.origin.y ?? 0
let duration:TimeInterval = (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0
let animationCurveRawNSN = userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber
let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIView.AnimationOptions.curveEaseInOut.rawValue
let animationCurve:UIView.AnimationOptions = UIView.AnimationOptions(rawValue: animationCurveRaw)
if endFrameY >= UIScreen.main.bounds.size.height {
self.textFieldBottomContraint?.constant = 0.0
} else {
self.textFieldBottomContraint?.constant = endFrame?.size.height ?? 0.0
}
UIView.animate(withDuration: duration,
delay: TimeInterval(0),
options: animationCurve,
animations: { self.view.layoutIfNeeded() },
completion: nil)
}
}
#objc func cancelAction()
{
self.inputField.resignFirstResponder()
}
#objc func doneAction()
{
self.inputField.resignFirstResponder()
}
deinit {
NotificationCenter.default.removeObserver(self)
}
}