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iOS Build an Interactive Story App with Swift Personalizing the Story Modifying Constraints

Qasa Lee
Qasa Lee
18,915 Points

How to understand "func keyboardWillShow(_ notification: Notification)" be called in the selector without parameter?

I know in the #selector() we just have to pass in the name of the method we're calling, but how can keyboardWillShow(_ notification: Notification) know the notification without giving any clue? NotificationCenter.default.addObserver(self, selector: #selector(self.keyboardWillShow), name: Notification.Name.UIKeyboardWillShow, object: nil) the code above can send the exact notification to the function keyboardWillShow()?! Or just because the #selector(self.keyboardWillShow) can grab the notification since it knows this comes from UIKeyboardWillShow ?!