Enabling done button after inserting one char in a textfield: textFieldDidEndEditing: or textFieldShouldBeginEditing: or?

Question

I would like to enable the done button on the navbar (in a modal view) when the user writes at least a char in a uitextfield. I tried:

• textFieldDidEndEditing:

Answer 1

Swift 2.2

You can assign custom method "checkTextField()" to "myTextField" UITextField as:

myTextField.addTarget(self, action: #selector(self.checkTextField(_:)), forControlEvents: .EditingChanged);

and toggle the done button inside the method as:

func checkTextField(sender: UITextField) {

    doneButton.enabled = !sender.hasText();
}

No need of any delegate.