Question

对于NSLayoutConstraint类，我有以下代码。该类帮助我在键盘出现时移动视图。很好，可以用。

但是以某种方式，当我将此类分配给约束并且键盘可见时，只要可见，就不能单击按钮。

我经历过这是因为我有另一段代码，可以在敲击键盘时隐藏键盘-卸下键盘后，只要能看到键盘，就可以点击按钮，但这带来了另一个问题，即键盘轻敲一下就不会消失。

是否可以将两者结合在一起，以便移动视图，但是如果我轻按一下，键盘会再次消失。

点击时：

extension UIViewController {
    func hideKeyboardWhenTappedAround() {
        let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(UIViewController.dismissKeyboard))
        tap.cancelsTouchesInView = false
        view.addGestureRecognizer(tap)
    }

    @objc func dismissKeyboard() {
        view.endEditing(true)
    }
}

移动视图：

import UIKit

#if !os(tvOS)
@available(tvOS, unavailable)
public class KeyboardLayoutConstraint: NSLayoutConstraint {

    private var offset : CGFloat = 0
    private var keyboardVisibleHeight : CGFloat = 0

    @available(tvOS, unavailable)
    override public func awakeFromNib() {
        super.awakeFromNib()

        offset = constant

        NotificationCenter.default.addObserver(self, selector: #selector(KeyboardLayoutConstraint.keyboardWillShowNotification(_:)), name: UIWindow.keyboardWillShowNotification, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(KeyboardLayoutConstraint.keyboardWillHideNotification(_:)), name: UIWindow.keyboardWillHideNotification, object: nil)
    }

    deinit {
        NotificationCenter.default.removeObserver(self)
    }

    // MARK: Notification

    @objc func keyboardWillShowNotification(_ notification: Notification) {
        if let userInfo = notification.userInfo {
            if let frameValue = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue {
                let frame = frameValue.cgRectValue
                keyboardVisibleHeight = frame.size.height / 2
            }

            self.updateConstant()
            switch (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber, userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber) {
            case let (.some(duration), .some(curve)):

                let options = UIView.AnimationOptions(rawValue: curve.uintValue)

                UIView.animate(
                    withDuration: TimeInterval(duration.doubleValue),
                    delay: 0,
                    options: options,
                    animations: {
                        UIApplication.shared.keyWindow?.layoutIfNeeded()
                        return
                }, completion: { finished in
                })
            default:

                break
            }

        }

    }

    @objc func keyboardWillHideNotification(_ notification: NSNotification) {
        keyboardVisibleHeight = 0
        self.updateConstant()

        if let userInfo = notification.userInfo {

            switch (userInfo[UIResponder.keyboardAnimationDurationUserInfoKey] as? NSNumber, userInfo[UIResponder.keyboardAnimationCurveUserInfoKey] as? NSNumber) {
            case let (.some(duration), .some(curve)):

                let options = UIView.AnimationOptions(rawValue: curve.uintValue)

                UIView.animate(
                    withDuration: TimeInterval(duration.doubleValue),
                    delay: 0,
                    options: options,
                    animations: {
                        UIApplication.shared.keyWindow?.layoutIfNeeded()
                        return
                }, completion: { finished in
                })
            default:
                break
            }
        }
    }

    func updateConstant() {
        self.constant = (offset - keyboardVisibleHeight)
    }

}
#endif

Answer 1

如果您可以使用第三方库，请先结帐：

https://github.com/hackiftekhar/IQKeyboardManager

此库非常有用且高度可定制，可以立即完成工作。

当键盘出现时移动视图，并在轻击时再次隐藏

1 个答案: