ios - 键盘通知

Question

我正在尝试使用键盘扩展从 userInfo 获取键盘大小。

我加

NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardDidShowNotification, object: nil)

在我的 KeyboardViewController.swift 中，但是 keyboardWillShow 永远不会被调用。

Answer 1

先注册键盘通知

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)

    let notificationCenter = NSNotificationCenter.defaultCenter()
    notificationCenter.addObserver(self, selector: "keyboardWillShow:", name: UIKeyboardWillShowNotification, object: nil)
    notificationCenter.addObserver(self, selector: "keyboardWillHide:", name: UIKeyboardWillHideNotification, object: nil)
}

override func viewDidDisappear(animated: Bool) {
    super.viewDidDisappear(animated)

    let notificationCenter = NSNotificationCenter.defaultCenter()
    notificationCenter.removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
    notificationCenter.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
}

然后

func keyboardWillShow(notification: NSNotification) {
    let userInfo = notification.userInfo!
    let keyboardHeight = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().height
}

并且您将高度值作为 CGFloat