NSNotfication.addObserver - 更新到当前的Swift语法？

Question

但是，目前在教程中，某些语法已过时。代码基本上应该显示并隐藏用户键盘。我用addObserver方法得到了一些语法错误，Swift希望我使用关键路径，但是，如果我使用自动'修复 - 它'我得到更多的错误。任何人都可以帮我解决这个问题吗？谢谢！

NSNotification.addObserver(self, selector: #selector(keyboardwillShow), name: .UIKeyboardWillShow, nil)  
NSNotification.addObserver(self, selector: #selector(keyboardwillHide), name: .UIKeyboardWillHide, nil) 


func keyboardwillShow(_notification:NSNotification) {  
    keyboard = (_notification.userInfo![UIKeyboardFrameEndUserInfoKey]! as AnyObject).cgRectValue 
    UIView.animate(withDuration: 0.4) { 
     self.scrolledView.frame.size.height = self.scrollViewHeight - self.keyboard.height 
    } 
} 

func keyboardwillHide(_notification:NSNotification) { 
    UIView.animate(withDuration: 0.5) { 
     self.scrolledView.frame.size.height = self.view.frame.height 
    } 
} 

我得到的调试消息："Incorrect argument labels in call(have _selector:name, expected _forKeyPath:options:context"

Answer 1

你的函数参数，那就是缺少当您在观看

加它，你必须使用NotificationCenter.default.addObserver没有NotificationCenter.addObserver

let selectorForKeyBoardWillShow: Selector = #selector(ViewController.keyboardWillShow(_:)) 
let selectorForKeyBoardWillHide: Selector = #selector(ViewController.keyboardWillHide(_:)) 

    // MARK: - Functions 
override func viewDidLoad() { 
    super.viewDidLoad() 
    NotificationCenter.default.addObserver(self, selector: selectorForKeyBoardWillShow, name: NSNotification.Name.UIKeyboardWillShow, object: nil) 
    NotificationCenter.default.addObserver(self, selector: selectorForKeyBoardWillHide, name: NSNotification.Name.UIKeyboardWillHide, object: nil) 
} 


// MARK: Keyboard Observer 
func keyboardWillShow(_ notification: Notification) { 
} 

func keyboardWillHide(_ notification: Notification) { 
}