gistfile1.txt

- (void)showAlertWithTextField {
    
    UIAlertController *alertView = [UIAlertController alertControllerWithTitle:@"Menu"
                                                                       message:@"Select a menu"
                                                                preferredStyle:UIAlertControllerStyleAlert];
    
    [alertView addTextFieldWithConfigurationHandler:^(UITextField *textField) {
        //Customize the textField
        textField.placeholder = @"User name";
        textField.textColor = [UIColor whiteColor];
        textField.borderStyle = UITextBorderStyleRoundedRect;
        textField.backgroundColor = [UIColor colorWithRed:171/255 green:182/255 blue:255/255 alpha:0.5];
    }];
    
    [alertView addAction:[UIAlertAction actionWithTitle:@"ok"
                                                  style:UIAlertActionStyleDefault
                                                handler:^(UIAlertAction *action) {
                                                    NSLog(@"action - %@", action.title);//callback
                                                }]];
    
    [self presentViewController:alertView animated:YES completion:^{
        NSLog(@"completed");
    }];
}

create an Alert with a TextField.