how to add an action on UITextField return key?

Ensure “self” subscribes to UITextFieldDelegate and initialise inputText with:

self.inputText.delegate = self;

Add the following method to “self”:

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
    if (textField == self.inputText) {
        [textField resignFirstResponder];
        return NO;
    }
    return YES;
}

Or in Swift:

func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    if textField == inputText {
        textField.resignFirstResponder()
        return false
    }
    return true
}