textfield auto focus not working properly - ios

Question

I have 6 text field text box. And when user finish enter in first text field, then it should automatically have to go second and so on. Here my code hats not working. when i enter the value in first text field, the values is entering in second ..here my code :
This below code i have done to enter only one digit in each text field. But here how can i add the text field responder...once i finish with first text field, adn so on...
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
if textField == self.cardTextFieldOne{
guard let text = textField.text else {return true}
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}else if textField == self.cardTextFieldTwo{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldTwo{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldThree{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldFour{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldFive{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldSix{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 1
}
else if textField == self.cardTextFieldMonth{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 2
}
else if textField == self.cardTextFieldYear{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
return newLength <= 2
}
return true
}
Thanks in advance !!
Update
if textField == self.cardTextFieldOne{
guard let text = textField.text else {return true}
let newLength = text.characters.count + string.characters.count - range.length
if (string == "") || string.characters.count < 1
{
return true //This also allow you to backspace
}else if (cardTextFieldOne.text?.characters.count)! >= 1
{
cardTextFieldOne.resignFirstResponder();
self.cardTextFieldTwo.becomeFirstResponder()
return false
}
return newLength <= 1
}

Answer 1

Simple Solution
Create Method which called every time you change the textField text like below you can see in the Image, while you right click on textfield, you see the Editing change drag it and create method like
#IBAction func editing(_ sender: UITextField)
{
if sender == yourFirstTextField {
if sender.text?.characters.count == 1 {
yourNextTextField.becomeFirstResponder()
}
}
}

Answer 2

Try using textField's delegate method
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
if textField == self.cardTextFieldOne{
textField.resignFirstResponder();
self.cardTextFieldTwo.becomeFirstResponder();
return false;
}else if textField == self.cardTextFieldTwo{
textField.resignFirstResponder();
self.cardTextFieldThree.becomeFirstResponder()
// if this is last field then return true
return true
}
}

Answer 3

Try to respond manually while textfield fill with single text.
if textField == self.cardTextFieldTwo{
guard let text = textField.text else { return true }
let newLength = text.characters.count + string.characters.count - range.length
if textField.text?.utf16.count==1 { // adjust your condition here
textField.resignFirstResponder()
self.cardTextFieldTwo.becomeFirstResponder()
}
return newLength <= 1
}
Note do this for all textfield

Answer 4

Use textFieldDidEndEditing method, than just call becomeFirstResponder() on next textField
func textFieldDidEndEditing(_ textField: UITextField) {
textField.becomeFirstResponder()
}