擴展iOS 11安全區域以包含鍵盤

Question

iOS 11中引入的新安全區域佈局指南非常適合防止內容在條形圖下顯示，但不包括鍵盤。這意味着當鍵盤顯示時，內容仍然隱藏在它後面，這是我正在試圖解決的問題。

我的方法是基於聆聽鍵盤通知，然後通過additionalSafeAreaInsets調整安全區域。

這裏是我的代碼：

override func viewDidLoad() { 
    let notificationCenter = NotificationCenter.default 
    notificationCenter.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil) 
    notificationCenter.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil) 
    notificationCenter.addObserver(self, selector: #selector(keyboardWillChange(notification:)), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil) 
} 

//MARK: - Keyboard 
extension MyViewController { 
    @objc func keyboardWillShow(notification: NSNotification) { 
     let userInfo = notification.userInfo! 
     let keyboardHeight = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue.height 

     additionalSafeAreaInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight, right: 0) 
     UIView.animate(withDuration: 0.3) { 
      self.view.layoutIfNeeded(); 
     } 
    } 

    @objc func keyboardWillHide(notification: NSNotification) { 
     additionalSafeAreaInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0) 
     UIView.animate(withDuration: 0.3) { 
      self.view.layoutIfNeeded(); 
     } 
    } 

    @objc func keyboardWillChange(notification: NSNotification) { 
     let userInfo = notification.userInfo! 
     let keyboardHeight = (userInfo[UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue.height 

     additionalSafeAreaInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight, right: 0) 

     UIView.animate(withDuration: 0.3) { 
      self.view.layoutIfNeeded(); 
     } 
    } 
} 

這個工程還有MyController是UIViewController與通過整個安全區延伸UITableView。現在，當鍵盤出現時，底部被向上推，使得鍵盤後面沒有單元格。

問題在於底部酒吧。我在底部還有一個已經包含在安全區域的工具欄。因此，將全鍵盤高度設置爲額外的安全區域插入，將桌面視圖的底部向上推到底部杆的高度。要使此方法正常工作，我必須將additionalSafeAreaInsets.bottom設置爲等於鍵盤高度減去底部條的高度。

問題1：在底部獲得當前安全區域缺口的最佳方法是什麼？手動獲取工具欄的框架並使用其高度？或者是否有可能直接從安全區域佈局指南中獲得差距？

問題2：假設底部欄應該可以改變大小，而不用更改鍵盤大小，所以我還應該實現一些方法來監聽欄中的變化。這最好在viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator)完成嗎？或者其他地方

謝謝

Answer 1

什麼，似乎是爲我工作是計算和鍵盤邊框view.safeAreaLayoutGuide.layoutFrame之間的交點，然後設定的高度爲additionalSafeAreaInsets.bottom，而不是整個鍵盤架高度。我在視圖控制器中沒有工具欄，但是我有一個標籤欄，並且正確說明了它。

完整代碼：

extension UIViewController { 

    func startAvoidingKeyboard() { 
     NotificationCenter.default.addObserver(self, 
               selector: #selector(_onKeyboardFrameWillChangeNotificationReceived(_:)), 
               name: NSNotification.Name.UIKeyboardWillChangeFrame, 
               object: nil) 
    } 

    func stopAvoidingKeyboard() { 
     NotificationCenter.default.removeObserver(self, 
                name: NSNotification.Name.UIKeyboardWillChangeFrame, 
                object: nil) 
    } 

    @objc private func _onKeyboardFrameWillChangeNotificationReceived(_ notification: Notification) { 
     guard let userInfo = notification.userInfo, 
      let keyboardFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else { 
       return 
     } 

     let keyboardFrameInView = view.convert(keyboardFrame, from: nil) 
     let safeAreaFrame = view.safeAreaLayoutGuide.layoutFrame.insetBy(dx: 0, dy: -additionalSafeAreaInsets.bottom) 
     let intersection = safeAreaFrame.intersection(keyboardFrameInView) 

     let animationDuration: TimeInterval = (notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0 
     let animationCurveRawNSN = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber 
     let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIViewAnimationOptions.curveEaseInOut.rawValue 
     let animationCurve = UIViewAnimationOptions(rawValue: animationCurveRaw) 

     UIView.animate(withDuration: animationDuration, delay: 0, options: animationCurve, animations: { 
      self.additionalSafeAreaInsets.bottom = intersection.height 
      self.view.layoutIfNeeded() 
     }, completion: nil) 
    } 
} 

Answer 2

如果您需要幫助回到前IOS11的版本，你可以 從法比奧使用的功能，並添加：

if #available(iOS 11.0, *) { } 

最終的解決方案：

extension UIViewController { 

    func startAvoidingKeyboard() { 
     NotificationCenter.default.addObserver(self, 
               selector: #selector(_onKeyboardFrameWillChangeNotificationReceived(_:)), 
               name: NSNotification.Name.UIKeyboardWillChangeFrame, 
               object: nil) 
    } 

    func stopAvoidingKeyboard() { 
     NotificationCenter.default.removeObserver(self, 
                name: NSNotification.Name.UIKeyboardWillChangeFrame, 
                object: nil) 
    } 

    @objc private func _onKeyboardFrameWillChangeNotificationReceived(_ notification: Notification) { 
     if #available(iOS 11.0, *) { 

      guard let userInfo = notification.userInfo, 
       let keyboardFrame = (userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else { 
        return 
      } 

      let keyboardFrameInView = view.convert(keyboardFrame, from: nil) 
      let safeAreaFrame = view.safeAreaLayoutGuide.layoutFrame.insetBy(dx: 0, dy: -additionalSafeAreaInsets.bottom) 
      let intersection = safeAreaFrame.intersection(keyboardFrameInView) 

      let animationDuration: TimeInterval = (notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber)?.doubleValue ?? 0 
      let animationCurveRawNSN = notification.userInfo?[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber 
      let animationCurveRaw = animationCurveRawNSN?.uintValue ?? UIViewAnimationOptions.curveEaseInOut.rawValue 
      let animationCurve = UIViewAnimationOptions(rawValue: animationCurveRaw) 

      UIView.animate(withDuration: animationDuration, delay: 0, options: animationCurve, animations: { 
       self.additionalSafeAreaInsets.bottom = intersection.height 
       self.view.layoutIfNeeded() 
      }, completion: nil) 
     } 
    } 
}