ios - Swift-在显示时通过键盘移动textField

出现时，我需要在键盘上移动文本字段。

我正在使用以下代码:

override func viewDidLoad() {
    super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(self.keyBoardWillShow(_:)), name: .UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(self.keyBoardWillHide(_:)), name: .UIKeyboardWillHide, object: nil)
}

接着:

@objc func keyBoardWillShow(_ notification: NSNotification) {
    let userInfo:NSDictionary = notification.userInfo! as NSDictionary
    let keyboardFrame:NSValue = userInfo.value(forKey: UIKeyboardFrameEndUserInfoKey) as! NSValue
    let keyboardRectangle = keyboardFrame.cgRectValue
    let keyboardHeight = keyboardRectangle.height

    UIView.animate(withDuration: 0.4) {
        self.commentViewBottomConstraint.constant = keyboardHeight
        self.view.layoutIfNeeded()
    }
}
@objc func keyBoardWillHide(_ notification: NSNotification) {
    UIView.animate(withDuration: 0.4) {
        self.commentViewBottomConstraint.constant = 0
        self.view.layoutIfNeeded()
    }
}

问题是似乎键盘高度不正确。实际上，视图的底部与键盘不对齐。视图和键盘之间有一个空间。



老实说我不明白我在做什么错...

感谢您的帮助!

最佳答案

我认为问题在于事实是底部约束相对于安全区域。
所以我通过添加以下内容修复了它:

let safeAreaHeight = self.view.safeAreaInsets.bottom
self.commentViewBottomConstraint.constant = keyboardHeight - safeAreaHeight

这是完整的代码:

 @objc func keyBoardWillShow(_ notification: NSNotification) {
    let userInfo:NSDictionary = notification.userInfo! as NSDictionary
    let keyboardFrame:NSValue = userInfo.value(forKey: UIKeyboardFrameEndUserInfoKey) as! NSValue
    let keyboardRectangle = keyboardFrame.cgRectValue
    let keyboardHeight = keyboardRectangle.height
    let safeAreaHeight = self.view.safeAreaInsets.bottom

    UIView.animate(withDuration: 0.4) {
        self.commentViewBottomConstraint.constant = keyboardHeight - safeAreaHeight
        self.view.layoutIfNeeded()
    }
}