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Gonzalo Nunez
Courses Plus Student 5,064 Pointscount the length of a String - Swift Delegate
Hi, in the video, count is done like this:
func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
let length = count(textField.text) - range.length + count(string) // but this error occurred: "Cannot invoke 'count' with an argument list of type '(String?)'"
if length > 0 {
submitButton.enabled = true
} else {
submitButton.enabled = false
}
return true
}
what I do?
2 Answers

Eduardo Pinheiro
4,649 PointsIf you're using Xcode 7, you need to change 'count(textField.text)' to 'textField.text!.characters.count' and 'count(string)' to 'string.characters.count'.

gurminder thind
Courses Plus Student 10,062 PointsCorrect code for Xcode 8.1 is
()
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool { let length = (textField.text?.characters.count)! - range.length + string.characters.count if length > 0 { submitButton.isEnabled = true } else { submitButton.isEnabled = false } return true }
(
)
Please note that count(textField.text) has been changed to (textField.text?.characters.count)! in Xcode 8.1 and also 'submitButton.enabled' has been changed to 'submitButton.isEnabled'. Again it will be nice if put in teacher's notes.