当键盘处于活动状态时，Swift阻止TabBar上移

NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_:)), name: UIResponder.keyboardWillShowNotification, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)

@objc func keyboardWillShow(_ notification: Notification) {
    if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
        let tabBarHeight = self.tabBarController?.tabBar.frame.size.height ?? 0
        let keyboardHeight = keyboardSize.height
        let tabBarFrame = self.tabBarController?.tabBar.frame
        self.tabBarController?.tabBar.frame = CGRect(x: tabBarFrame.origin.x, y: tabBarFrame.origin.y, width: tabBarFrame.width, height: tabBarHeight + keyboardHeight)
    }
}

@objc func keyboardWillHide(_ notification: Notification) {
    let tabBarHeight = self.tabBarController?.tabBar.frame.size.height ?? 0
    let tabBarFrame = self.tabBarController?.tabBar.frame
    self.tabBarController?.tabBar.frame = CGRect(x: tabBarFrame.origin.x, y: tabBarFrame.origin.y, width: tabBarFrame.width, height: tabBarHeight)
}