Making a Login screen similar to the lock screen

Question

Im trying to make a login screen similar to the lock screen with 4 textField. The problem i'm facing is with changing the focus from one text field to the next.

• when i say secondTextField.becomeFirstResponder(), the value of the firstTextField gets copied to the secondTextField
• i'm using a decimal pad - keyboard type

Here is what i have done so far and i can't find a way around to fix the problem :

• Using UITextFieldDelegate
• made IBOutlet connection for all the textField
• firstText.delegate = self secondText.delegate = self thirdText.delegate = self firstText.becomeFirstResponder()

• func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool { var newLength = countElements(textField.text) + countElements(string) - range.length

      if newLength == 1 {
          if textField == firstText{
              changeFocus(textField)
          }else if textField == secondText {
              changeFocus(textField)
          }else if textField == thirdText {
              changeFocus(textField)
          }
  
      }
  return newLength <= 1
  

  }

  func changeFocus(nextFocus: UITextField){

  if nextFocus == firstText {
      firstText.resignFirstResponder()
      secondText.becomeFirstResponder()
  } else if nextFocus == secondText {
      secondText.resignFirstResponder()
      thirdText.becomeFirstResponder()
  } else if nextFocus == thirdText {
      thirdText.resignFirstResponder()
  }
  

  }

How can i do this correctly, any help and suggestion please.

Answer 1

Use this delegate method to change the focus

func textFieldShouldReturn(textField: UITextField) -> Bool

Answer 2

To add a little more to svrushal answer:

func textFieldShouldReturn(textField: UITextField) -> Bool {
   if textField == firstText {
       secondText.becomeFirstResponder()
   }

   if textField == secondText {
       thirdText.becomeFirstResponder()
   }

   if textField == thirdText {
       fourthText.becomeFirstResponder()
   }

}

Answer 3

you can refer this link https://github.com/dhennessy/PAPasscode/blob/master/PAPasscode/PAPasscodeViewController.h

it will help you out.

Answer 4

I found something similar here: similar

Got it to work, with two limitations :

• Firstly, I cant delete backwards
• Second, the user has to tap on the first textField if the passCode is wrong. But for now these is good enough.

• Here are the methods

  func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
  
  var shouldProcess = false
  var moveToNextTextField = false
  var insertStringLength = countElements(string)
  if insertStringLength == 0 {
      shouldProcess = true
  }
  else {
      if countElements(textField.text) == 0 {
          shouldProcess = true
      }
  }
  if shouldProcess {
     var myString = textField.text
      if countElements(myString) == 0{
          myString = myString + string
  
          password = password + myString
          moveToNextTextField = true
      }
      textField.text = myString
  
      if moveToNextTextField {
          changeFocus(textField)
      }
  }
  return false
  }
  

• method to change the focus :

  func changeFocus(nextTextField : UITextField){
  if  nextTextField == firstText {
      firstText.resignFirstResponder()
      secondText.becomeFirstResponder()
  } else if nextTextField == secondText {
      secondText.resignFirstResponder()
      thirdText.becomeFirstResponder()
  } else if nextTextField == thirdText {
      thirdText.resignFirstResponder()
      fourthText.becomeFirstResponder()
  } else if nextTextField == fourthText {
      fourthText.resignFirstResponder()
  }
  

  }

• Method to check the pin/passcode :

  func textFieldShouldEndEditing(textField: UITextField) -> Bool {
  if textField == fourthText {
     thirdText.resignFirstResponder()
      let pass = defaultUser.stringForKey(Admin)
      println("password = \(password)")
      if pass  == password {
  
          println("the password is correct")
          dispatch_async(dispatch_get_main_queue()) { () -> Void in
              self.performSegueWithIdentifier("SegueToSecond", sender: self)
          }
  
      } else {
          println("wrong password")
          thirdText.text = ""
          secondText.text = ""
          firstText.text = ""
          fourthText.text = ""
          password = ""
          view.reloadInputViews()
      }
  
  }
  
  return true
  }
  

Hope these help some one later on.