关于在文本字段中输入文本，我遇到了一个奇怪的问题。我目前正在使用下面的代码。我的代码是根据答案 here 建模的.

class RocketViewController: UIViewController, UITableViewDelegate, UITableViewDataSource, UITextFieldDelegate, NSFetchedResultsControllerDelegate {

   var offsetY:CGFloat = 0

   override func viewDidLoad() {
    super.viewDidLoad()

    NotificationCenter.default.addObserver(self, selector: #selector(RocketViewController.keyboardFrameChangeNotification(notification:)), name: NSNotification.Name.UIKeyboardWillChangeFrame, object: nil)
    }

    @objc func keyboardFrameChangeNotification(notification: Notification) {
    if let userInfo = notification.userInfo {
        let keyBoardFrame = userInfo[UIKeyboardFrameEndUserInfoKey] as? CGRect
        let animationDuration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as? Double ?? 0
        let animationCurveRawValue = (userInfo[UIKeyboardAnimationCurveUserInfoKey] as? Int) ?? Int(UIViewAnimationOptions.curveEaseInOut.rawValue)
        let animationCurve = UIViewAnimationOptions(rawValue: UInt(animationCurveRawValue))
        if let _ = keyBoardFrame, keyBoardFrame!.intersects(self.mainStackView.frame) {
            self.offsetY = self.mainStackView.frame.maxY - keyBoardFrame!.minY
            UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
                self.mainStackView.frame.origin.y = self.mainStackView.frame.origin.y - self.offsetY
                self.rocketSelectTable.frame.origin.y = self.rocketSelectTable.frame.origin.y - self.offsetY
            }, completion: nil)
        } else {
            if self.offsetY != 0 {
                UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
                    self.mainStackView.frame.origin.y = self.mainStackView.frame.origin.y + self.offsetY
                    self.rocketSelectTable.frame.origin.y = self.rocketSelectTable.frame.origin.y + self.offsetY
                    self.offsetY = 0
                  }, completion: nil)
               }
           }
       }
   }
}

在我看来，我有一个 TableView ，其中一个获取的结果 Controller 作为其数据源，下面是堆栈 View 中的文本字段，称为 mainStackView，它们最终保存在核心数据存储中。

无论是计算第一响应者的偏移量，还是简单地计算堆栈 View ，我都对这段代码进行了多次迭代，结果相同。当文本字段成为第一响应者时， View 会随着键盘很好地向上滑动。但是，一旦我尝试在该字段中键入内容， View 就会快速回到其原始位置。我确定我犯了一个新手错误，但我无法弄清楚我做错了什么，而且我在搜索中没有发现任何东西，除了 android 的类似问题。提前致谢。

最佳答案

虽然我还不确定为什么我会看到我在更改框架时看到的文本字段行为，但我可以通过使用 CGAffineTransform 来停止该行为。我的代码现在是:

  @objc func keyboardFrameChangeNotification(notification: Notification) {
       if let userInfo = notification.userInfo {
           let keyBoardFrame = userInfo[UIKeyboardFrameEndUserInfoKey] as? CGRect
           let animationDuration = userInfo[UIKeyboardAnimationDurationUserInfoKey] as? Double ?? 0
           let animationCurveRawValue = (userInfo[UIKeyboardAnimationCurveUserInfoKey] as? Int) ?? Int(UIViewAnimationOptions.curveEaseInOut.rawValue)
           let animationCurve = UIViewAnimationOptions(rawValue: UInt(animationCurveRawValue))
           if let _ = keyBoardFrame, keyBoardFrame!.intersects(self.mainStackView.frame) {
               self.offsetY = self.mainStackView.frame.maxY - keyBoardFrame!.minY
               let transformUp = CGAffineTransform.init(translationX: 0, y: (0 - self.offsetY))
               UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
                   self.mainStackView.transform = transformUp
                   self.rocketSelectTable.transform = transformUp
               }, completion: nil)
           } else {
               if self.offsetY != 0 {
                   UIView.animate(withDuration: animationDuration, delay: TimeInterval(0), options: animationCurve, animations: {
                       self.mainStackView.transform = CGAffineTransform.identity
                       self.rocketSelectTable.transform = CGAffineTransform.identity
                       self.offsetY = 0
                   }, completion: nil)
               }
           }
       }

此代码流畅地动画 View 的移动，并且在文本字段中键入时不会快速返回到原始位置。我希望这对其他人有帮助。

关于ios - 在文本字段中输入文本后，文本字段会下降到键盘下方，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/49795957/