滑动到 popViewController 在 iOS 13 中不起作用

Question

下面的代码，我已经完成了滑动到 popViewController 的操作。 这适用于 ios 12 或更早版本，但是当它在 iOS 13 中运行时，它不起作用。 Xcode 的当前版本是 11.1

另外，我正在使用本机 NavigationController 和导航栏。 所以我不认为这是因为导航 controller 的问题。

import UIKit

class SwipeNavigationController: UINavigationController {

    // MARK: - Lifecycle

    override init(rootViewController: UIViewController) {
        super.init(rootViewController: rootViewController)
    }

    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)

        self.setup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        self.setup()
    }

    private func setup() {
        delegate = self
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        // This needs to be in here, not in init
        interactivePopGestureRecognizer?.delegate = self
    }

    deinit {
        delegate = nil
        interactivePopGestureRecognizer?.delegate = nil
    }

    // MARK: - Overrides

    override func pushViewController(_ viewController: UIViewController, animated: Bool) {
        duringPushAnimation = true

        super.pushViewController(viewController, animated: animated)
    }

    // MARK: - Private Properties

    fileprivate var duringPushAnimation = false
}

// MARK: - UINavigationControllerDelegate

extension SwipeNavigationController: UINavigationControllerDelegate {

    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
        guard let swipeNavigationController = navigationController as? SwipeNavigationController else { return }

        swipeNavigationController.duringPushAnimation = false
    }

}

// MARK: - UIGestureRecognizerDelegate

extension SwipeNavigationController: UIGestureRecognizerDelegate {

    func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        guard gestureRecognizer == interactivePopGestureRecognizer else {
            return true // default value
        }
        // Disable pop gesture in two situations:
        // 1) when the pop animation is in progress
        // 2) when user swipes quickly a couple of times and animations don't have time to be performed
      if (self.visibleViewController?.isKind(of: CheckOTPViewController.self))! {
        return false
      }
      if (self.visibleViewController?.isKind(of: ForgotPasswordViewController.self))! {
        return false
      }

        return viewControllers.count > 1 && duringPushAnimation == false
    }
}

Answer 1

您可以尝试使用以下检查 iOS 13 的条件来检查弹出视图 controller：

 if #available(iOS 13.0, *) {
                   self.navigationController?.popToViewController(vc as! YourVC, animated: true)
                } else {
                    // Fallback on earlier versions

                }

您必须查看 iOS 13 带来的 UINavigationController 更改：

https://medium.com/@hacknicity/view-controller-presentation-changes-in-ios-13-ac8c901ebc4e

Answer 2

经过大量 try-catch 之后，我终于解决了这个问题。 问题是调用 deinit 方法并且没有在 viewDidLoad 方法上设置正确的委托。

现在下面是工作代码。

import UIKit

class SwipeNavigationController: UINavigationController {

    // MARK: - Lifecycle

    override init(rootViewController: UIViewController) {
        super.init(rootViewController: rootViewController)
    }

    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)

        self.setup()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        self.setup()
    }

    private func setup() {
        delegate = self
        interactivePopGestureRecognizer?.delegate = self
        navigationItem.backBarButtonItem?.isEnabled = true
        interactivePopGestureRecognizer?.isEnabled = true
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        // This needs to be in here, not in init
        setup()
    }

    // MARK: - Overrides

    override func pushViewController(_ viewController: UIViewController, animated: Bool) {
        duringPushAnimation = true

        super.pushViewController(viewController, animated: animated)
    }

    // MARK: - Private Properties

    fileprivate var duringPushAnimation = false
}

// MARK: - UINavigationControllerDelegate

extension SwipeNavigationController: UINavigationControllerDelegate {

    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
        guard let swipeNavigationController = navigationController as? SwipeNavigationController else { return }

        swipeNavigationController.duringPushAnimation = false
    }

}

// MARK: - UIGestureRecognizerDelegate

extension SwipeNavigationController: UIGestureRecognizerDelegate {

    func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        guard gestureRecognizer == interactivePopGestureRecognizer else {
            return true // default value
        }
        // Disable pop gesture in two situations:
        // 1) when the pop animation is in progress
        // 2) when user swipes quickly a couple of times and animations don't have time to be performed
      if (self.visibleViewController?.isKind(of: CheckOTPViewController.self))! {
        return false
      }
      if (self.visibleViewController?.isKind(of: ForgotPasswordViewController.self))! {
        return false
      }

        return viewControllers.count > 1 && duringPushAnimation == false
    }
}