ios - how to segue a textfield on the same view controller (swift 3) -

i have 2 textfields. ever entered in textfield displayed in textfield b. textfield b used display. user can enter name in textfield a. user enters name in textfield , displayed in textfield b.

    import uikit  class viewcontroller: uiviewcontroller {  @iboutlet var a: uitextfield! @iboutlet var b: uitextfield! override func viewdidload() {     super.viewdidload()     // additional setup after loading view, typically nib.      b.isenabled = false    }  override func didreceivememorywarning() {     super.didreceivememorywarning()     // dispose of resources can recreated. }} 

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import uikit  class viewcontroller: uiviewcontroller { @iboutlet weak var a: uitextfield! @iboutlet weak var b: uitextfield!  override func viewdidload() {     super.viewdidload()     // additional setup after loading view, typically nib.     b.isenabled = false }  override func didreceivememorywarning() {     super.didreceivememorywarning()     // dispose of resources can recreated. }   }  // use extensions code clear  // uitextfield delegate extension viewcontroller: uitextfielddelegate { func textfielddidendediting(_ textfield: uitextfield) {     // if have many textfields , user dismissed keyboard or tapped other textfield     if textfield === {         b.text = textfield.text     } }  // if user clicked return key in keyboard func textfieldshouldreturn(_ textfield: uitextfield) -> bool {     // works if have , b textfields     // b.text = textfield.text      // use if statment if have many text fields     if textfield === {         b.text = textfield.text     }     return true }  func textfield(_ textfield: uitextfield, shouldchangecharactersin range: nsrange, replacementstring string: string) -> bool {     // if want see text changes live user clicks button     b.text = textfield.text      return true   }  } 

don't forget connect textfields delegate storyboard or nib whatever using