How to auto fetch OTP, if we use multiple text fields

Question

I know that if we want to auto fetch the OTP(if we use single textfield) we need to use

otpTextField.textContentType = .oneTimeCode

But, If we use multiple textfield(According to following image)

how should we achieve this ?

Answer 1

If you can get the auto OTP for single field, you can split that text into your four text fields. I believe.

You may have to use textField's change observer as like below,

textField.addTarget(self, action: #selector(textFieldDidChange(_:)), for: .editingChanged)
func textFieldDidChange(_ textField: UITextField) {

        // here check you text field's input Type
        if textField.textContentType == UITextContentType.oneTimeCode{

            //here split the text to your four text fields

            if let otpCode = textField.text, otpCode.count > 3{

                textField.text = String(otpCode[otpCode.startIndex])
                textField1.text = String(otpCode[otpCode.index(otpCode.startIndex, offsetBy: 1)])
                textField2.text = String(otpCode[otpCode.index(otpCode.startIndex, offsetBy: 2)])
                textField3.text = String(otpCode[otpCode.index(otpCode.startIndex, offsetBy: 3)])
        }
    }

}

Answer 2

What I do is similar to @Natarajan's answer, but I use UITextFieldDelegate method. On viewDidAppear your first text field should become first responder and be of type oneTimeCode.

func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {        
    // Fill your textfields here

    return true
}