How set swift 3 UITextField border color?

Try to use this, It might be helpful to you

let myColor : UIColor = UIColor( red: 0.5, green: 0.5, blue:0, alpha: 1.0 )
myTextField.layer.masksToBounds = true
myTextField.layer.borderColor = myColor.CGColor
myTextField.layer.borderWidth = 2.0

You also need to set border width, because your border color is set already but your default border width is 0.0 so you can't see it.

So, set border width something like,

  email.layer.borderWidth = 1.0

Update :

Your code should be like,

 @IBOutlet weak var email: UITextField!
 @IBOutlet weak var pass: UITextField!

 override func viewDidLoad() {
   super.viewDidLoad()

   let myColor = UIColor.white
   email.layer.borderColor = myColor.cgColor
   pass.layer.borderColor = myColor.cgColor

   email.layer.borderWidth = 1.0
   pass.layer.borderWidth = 1.0

}

Use the below code in swift 3:

in view did load

 outer_line.layer.borderWidth = 1
 outer_line.layer.borderColor = UIColor.lightGray.cgColor

I think you should first provide a borderWidth

@IBOutlet weak var email: UITextField!
@IBOutlet weak var pass: UITextField!


override func viewDidLoad() {
super.viewDidLoad()

let myColor : UIColor = UIColor.white()
email.layer.borderWidth = 1
email.layer.borderColor = myColor.cgColor
pass.layer.borderColor = myColor.cgColor


}

and then set a color :)