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I have been trying to limit a textField by many codes available out there in the internet but with no luck. I have added UIViewController<UITextFieldDelegate> in my header file and textField.delegate = self; in my viewDidLoad and implemented the following fundtion in my .m file: - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string { NSString *newString = [textField.text stringByReplacingCharactersInRange:range withString:string]; return !([newString length] > 5); } this stil does not limit my text field. any idea?

I have created a custom keyboard and I have two text fields. When the user clicks on one of them, the keyboard appears. How can I know which text field is currently active so that I write what the user is typing from the keyboard?