How to move content of UIViewController upwards as Keypad appears using Swift

Question

I want to move the content of the bottom of my UIViewController upwards as the keypad appears. At the bottom of the view controller I have a UITextField and when the user cl

Answer 1

I'm not sure how the top rated answer works; isn't it supposed to be:

func keyboardWillShow(notification: NSNotification) {
    if let info: NSDictionary = notification.userInfo {
        let value: NSValue = info.valueForKey(UIKeyboardFrameEndUserInfoKey) as NSValue
        let rect: CGRect = value.CGRectValue()
        view_comment.y = rect.height - view_comment.h
    }
}

Since you need to cast Dictionary to NSDictionary in order to access valueForkey?