UITextViewDelegate has a very useful method: -textViewDidChange:. As the name implies, text view calls this method on its delegate whenever the text it is currently presenting is changed.
But, unlike UITextViewDelegate, UITextFieldDelegate doesn’t have such a method. Instead, it has a hidden gem that provides the same functionality.
UIControlEventEditingChangedMeet our hero! You can either assign an IBAction for this event in Interface Builder or add a target and action in code.
[self.textField addTarget:self action:@selector(textFieldDidChangeText:) forControlEvents:UIControlEventEditingChanged];
- (IBAction)textFieldDidChangeText:(UITextField *)textField {
NSLog(@“Updated text: %@”, textField.text);
}This way, whenever a change appears on text field, it will call the action method assigned for
UIControlEventEditingChangedevent.