swift 出现键盘时 UITableView 向上滚动,但我看不到顶部单元格

swift UITableView scrolls up when keyboard appears but I can't see the top cells

我有一个带有 TableView 和 textView 的 ViewController。我正在使用以下代码,以便在出现键盘时将 textView 和 Tableview 向上推。

绑定到键盘

extension UIView {

    func bindToKeyboard(){
        NotificationCenter.default.addObserver(self, selector:
            #selector(UIView.keyboardWillChange(_:)), name:
            UIResponder.keyboardWillChangeFrameNotification, object: nil)
    }

    @objc func keyboardWillChange(_ notification: NSNotification) {
        let duration = notification.userInfo!
        [UIResponder.keyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIResponder.keyboardAnimationCurveUserInfoKey]
            as! UInt
        let curFrame = (notification.userInfo![UIResponder.keyboardFrameBeginUserInfoKey]
            as! NSValue).cgRectValue
        let targetFrame = (notification.userInfo![UIResponder.keyboardFrameEndUserInfoKey]
            as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options:
            UIView.KeyframeAnimationOptions(rawValue: curve), animations: {
                self.frame.origin.y += deltaY

        },completion: {(true) in
            self.layoutIfNeeded()
        })
    }
}

我遇到的问题是 tableView 中的顶部单元格,我无法向下滚动以显示它们,除非我关闭键盘。我一直在寻找可能的代码示例来解决这个问题,但我似乎找不到合适的解决方案。非常感谢任何输入。

解决方案

已将观察者添加到 viewDidLoad

let notificationCenter = NotificationCenter.default

notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillHideNotification, object: nil)

notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)

这已添加到 class

 @objc func adjustForKeyboard(notification: Notification) {

        guard let keyboardValue = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else { return }

        let keyboardScreenEndFrame = keyboardValue.cgRectValue

        let keyboardViewEndFrame = view.convert(keyboardScreenEndFrame, from: view.window)

        if notification.name == UIResponder.keyboardWillHideNotification {
            tableView.contentInset = .zero
        } else {
            //Modify the top insets to 350 and the height of the keyboard > 10 ? 10 : 10
            //to eliminate the gap between the bottom cell and the textView
            tableView.contentInset = UIEdgeInsets(top: 350, left: 0, bottom: keyboardViewEndFrame
                .height > 10 ? 10 : 10, right: 0)
        }
        tableView.scrollIndicatorInsets = tableView.contentInset
    }

希望这对任何人都有帮助。

您正在更改 table 视图的 frame,但您应该修改 contentOffsetcontentInsets 属性。

如果您移动框架,整个 table 将移出屏幕,因此顶部单元格也会移出屏幕。

有很多(我的意思是很多很多)教程可能对您有帮助,请参见例如https://www.hackingwithswift.com/example-code/uikit/how-to-adjust-a-uiscrollview-to-fit-the-keyboard

还有多种解决方案可以在例如github.

你也可以在你的项目中使用IQKeyboardManager cocoapod