swift 弹出键盘view自动上升

override func viewWillAppear(animated: Bool) {
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
    }

func keyboardWillShow(notification:NSNotification){if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
            //let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
            //let keyboardheight  = keyboardSize.height as CGFloat
            //let frame = self.nameInput.frame
            // frame.origin.y = frame.origin.y - keyboardheight
            //var offset = 156 as CGFloat
            var width = self.view.frame.size.width;
            var height = self.view.frame.size.height;
            let rect = CGRectMake(0.0, -156,width,height);
            self.view.frame = rect
        }
    }

func keyboardWillHide(notification:NSNotification){
        self.view.addSubview(logoArea)
        var width = self.view.frame.size.width;
        var height = self.view.frame.size.height;
        let rect = CGRectMake(0.0, 0,width,height);
        self.view.frame = rect
    }