swift 手势侧滑

大家所知 自定义导航栏返回图标后 侧滑失效   现贴下解决代码    

    var popDelegate: UIGestureRecognizerDelegate?

       self.popDelegate = self.interactivePopGestureRecognizer?.delegate

        self.delegate = self

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

        if viewControllers.count > 0 {

            viewController.hidesBottomBarWhenPushed = true

            viewController.navigationItem.leftBarButtonItem = UIBarButtonItem(image: UIImage(named: "lefterbackicon_titlebar_28x28_"), style: .plain, target: self, action: #selector(navigationBack))

            

            //实现滑动返回功能

            //清空滑动返回手势的代理就能实现

            if viewController == self.viewControllers[0] {

                self.interactivePopGestureRecognizer!.delegate = self.popDelegate

            }

            else {

                self.interactivePopGestureRecognizer!.delegate = nil

            }

        }

        super.pushViewController(viewController, animated: true)

    }