Try this :
Swift 3
self.promoTextField.keyboardType = UIKeyboardType.emailAddress
// Or Shorter version
self.promoTextField.keyboardType = .emailAddress
Swift < 3
self.promoTextField.keyboardType = UIKeyboardType.EmailAddress
Try this :
self.promoTextField.keyboardType = UIKeyboardType.emailAddress
// Or Shorter version
self.promoTextField.keyboardType = .emailAddress
self.promoTextField.keyboardType = UIKeyboardType.EmailAddress