语法2.2

NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(MusicViewController.keyboardWasShown(_:)), name: UIKeyboardDidShowNotification, object: nil)复制代码

语法2.0

NSNotificationCenter.defaultCenter().addObserver(self, selector:      "keyboardWillDisappear:", name:UIKeyboardWillHideNotification, object: nil)    func keyboardWasShown(notification: NSNotification) {  // 获取键盘信息  let keyboardinfo = notification.userInfo![UIKeyboardFrameBeginUserInfoKey]  let keyboardheight:CGFloat = (keyboardinfo?.CGRectValue.size.height)!  print("键盘弹起")  print(keyboardheight)复制代码

}

func keyboardWillDisappear(notification:NSNotification){

print("键盘落下")复制代码

}