ios - Swift:实例化 View Controller 以在当前导航堆栈中进行自定义转换

Question

介绍

我正在创建一个应用程序，在其 rootViewController 中有一个 UITableView 和一个 UIPanGestureRecognizer 附加到一个小的 UIView 作为“handle”，为名为“SlideOutViewController”的 UIViewController 启用自定义 View Controller 转换，以便从右侧平移。

问题

我注意到我的方法有两个问题。但实际的自定义转换按预期工作。

1. 当创建 SlideOutViewController 时，我相信它没有附加到导航堆栈，因此它没有关联的导航栏。如果我使用 navigationController 将其推送到堆栈上，我将失去交互式转换。

2. 旁注:我还没有找到将 handle 连接到交互拖出的 SlideOutViewController 的方法。所以 handle 的平移与SlideOutViewControllers的位置不一致。

问题

• 如何将 SlideOutViewController 添加到导航堆栈？这样当我触发 UIPanGestureRecognizer 时，SlideOutViewController 会随着 navigationBar 转换？

我的代码

在 rootViewController 中。

class RootViewController: UIViewController {

    ...

    let slideControllerHandle = UIView()
    var interactionController : UIPercentDrivenInteractiveTransition?

    override func viewDidLoad() {
        super.viewDidLoad()

        ... // Setting up the table view etc...

        setupPanGForSlideOutController()
    }

    private func setupPanGForSlideOutController() {
         slideControllerHandle.translatesAutoresizingMaskIntoConstraints = false
         slideControllerHandle.layer.borderColor = UIColor.black.cgColor
         slideControllerHandle.layer.borderWidth = 1
         slideControllerHandle.layer.cornerRadius = 30
         view.addSubview(slideControllerHandle)
         slideControllerHandle.frame = CGRect(x: view.frame.width - 12.5, y: view.frame.height / 2, width: 25, height: 60)
         let panGestureForCalendar = UIPanGestureRecognizer(target: self, action: #selector(handlePanGestureForSlideOutViewController(_:)))
         slideControllerHandle.addGestureRecognizer(panGestureForCalendar)
    }

    @objc private func handlePanGestureForSlideOutViewController(_ gesture: UIPanGestureRecognizer) {

         let xPosition = gesture.location(in: view).x
         let percent = 1 - (xPosition / view.frame.size.width)

         switch gesture.state {
         case .began:
             guard let slideOutController = storyboard?.instantiateViewController(withIdentifier: "CNSlideOutViewControllerID") as? SlideOutViewController else { fatalError("Sigh...") }
             interactionController = UIPercentDrivenInteractiveTransition()
        slideOutController.customTransitionDelegate.interactionController = interactionController
             self.present(slideOutController, animated: true)
         case .changed:
             slideControllerHandle.center = CGPoint(x: xPosition, y: slideControllerHandle.center.y)
             interactionController?.update(percent)
         case .ended, .cancelled:
             let velocity = gesture.velocity(in: view)
             interactionController?.completionSpeed = 0.999
             if percent > 0.5 || velocity.x < 10 {
                 UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations: {
                     self.slideControllerHandle.center = CGPoint(x: self.view.frame.width, y: self.slideControllerHandle.center.y)
                 })
                 interactionController?.finish()
             } else {
                 UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 0.5, options: .curveEaseInOut, animations: {
                     self.slideControllerHandle.center = CGPoint(x: -25, y: self.slideControllerHandle.center.y)
                 })
                 interactionController?.cancel()
             }
             interactionController = nil
         default:
             break
         }
    }

SlideOutViewController

class SlideOutViewController: UIViewController {

    var interactionController : UIPercentDrivenInteractiveTransition?
    let customTransitionDelegate = TransitionDelegate()

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        modalPresentationStyle = .custom
        transitioningDelegate = customTransitionDelegate
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .red
        navigationItem.title = "Slide Controller"
        let addButton = UIBarButtonItem(barButtonSystemItem: .add, target: self, action: #selector(addNewData(_:)))
        navigationItem.setRightBarButton(addButton, animated: true)
    }

}

自定义转换代码。 Based on Rob's descriptive answer on this SO question

1. 过渡代理

   class TransitioningDelegate: NSObject, UIViewControllerTransitioningDelegate {
   
       weak var interactionController : UIPercentDrivenInteractiveTransition?
       func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
           return CNRightDragAnimationController(transitionType: .presenting)
       }
   
       func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
           return CNRightDragAnimationController(transitionType: .dismissing)
       }
   
       func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
           return PresentationController(presentedViewController: presented, presenting: presenting)
       }
   
       func interactionControllerForPresentation(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
           return interactionController
       }    
   
       func interactionControllerForDismissal(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
           return interactionController
       }
   }
   

2. 拖动动画过渡

   class CNRightDragAnimationController: NSObject, UIViewControllerAnimatedTransitioning {
   
       enum TransitionType {
           case presenting
           case dismissing
       }
   
       let transitionType: TransitionType
   
       init(transitionType: TransitionType) {
           self.transitionType = transitionType
           super.init()
       }
   
       func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
           let inView   = transitionContext.containerView
           let toView   = transitionContext.view(forKey: .to)!
           let fromView = transitionContext.view(forKey: .from)!
   
           var frame = inView.bounds
   
           switch transitionType {
           case .presenting:
               frame.origin.x = frame.size.width
               toView.frame = frame
   
               inView.addSubview(toView)
               UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
                   toView.frame = inView.bounds
               }, completion: { finished in
                   transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
               })
           case .dismissing:
               toView.frame = frame
               inView.insertSubview(toView, belowSubview: fromView)
   
               UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
                   frame.origin.x = frame.size.width
                   fromView.frame = frame
               }, completion: { finished in
                   transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
               })
           }
       }
   
       func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
           return 0.5
       }
   }
   

3. 展示 Controller

   class PresentationController: UIPresentationController {
   
       override var shouldRemovePresentersView: Bool { return true }
   }
   

感谢阅读我的问题。

Answer 1

您从中获取的动画代码用于自定义“呈现”(例如模态)过渡。但是，如果您希望在使用导航 Controller 时在推送/弹出时自定义导航，您可以为 UINavigationController 指定一个委托(delegate)，然后在 navigationController(_:animationControllerFor:from:to:) 中返回适当的转换委托(delegate)。 .并实现 navigationController(_:interactionControllerFor:)并将您的交互 Controller 放回那里。

---

例如我会做类似的事情:

class FirstViewController: UIViewController {

    let navigationDelegate = CustomNavigationDelegate()

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationController?.delegate = navigationDelegate
        navigationDelegate.addPushInteractionController(to: view)
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        navigationDelegate.pushDestination = { [weak self] in
            self?.storyboard?.instantiateViewController(withIdentifier: "Second")
        }
    }
}

地点:

class CustomNavigationDelegate: NSObject, UINavigationControllerDelegate {

    var interactionController: UIPercentDrivenInteractiveTransition?
    var current: UIViewController?
    var pushDestination: (() -> UIViewController?)?

    func navigationController(_ navigationController: UINavigationController,
                              animationControllerFor operation: UINavigationController.Operation,
                              from fromVC: UIViewController,
                              to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        return CustomNavigationAnimator(transitionType: operation)
    }

    func navigationController(_ navigationController: UINavigationController,
                              interactionControllerFor animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
        return interactionController
    }

    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
        current = viewController
    }
}

// MARK: - Push

extension CustomNavigationDelegate {
    func addPushInteractionController(to view: UIView) {
        let swipe = UIScreenEdgePanGestureRecognizer(target: self, action: #selector(handlePushGesture(_:)))
        swipe.edges = [.right]
        view.addGestureRecognizer(swipe)
    }

    @objc private func handlePushGesture(_ gesture: UIScreenEdgePanGestureRecognizer) {
        guard let pushDestination = pushDestination else { return }

        let position = gesture.translation(in: gesture.view)
        let percentComplete = min(-position.x / gesture.view!.bounds.width, 1.0)

        switch gesture.state {
        case .began:
            interactionController = UIPercentDrivenInteractiveTransition()
            guard let controller = pushDestination() else { fatalError("No push destination") }
            current?.navigationController?.pushViewController(controller, animated: true)

        case .changed:
            interactionController?.update(percentComplete)

        case .ended, .cancelled:
            let speed = gesture.velocity(in: gesture.view)
            if speed.x < 0 || (speed.x == 0 && percentComplete > 0.5) {
                interactionController?.finish()
            } else {
                interactionController?.cancel()
            }
            interactionController = nil

        default:
            break
        }
    }
}

// MARK: - Pop

extension CustomNavigationDelegate {
    func addPopInteractionController(to view: UIView) {
        let swipe = UIScreenEdgePanGestureRecognizer(target: self, action: #selector(handlePopGesture(_:)))
        swipe.edges = [.left]
        view.addGestureRecognizer(swipe)
    }

    @objc private func handlePopGesture(_ gesture: UIScreenEdgePanGestureRecognizer) {
        let position = gesture.translation(in: gesture.view)
        let percentComplete = min(position.x / gesture.view!.bounds.width, 1)

        switch gesture.state {
        case .began:
            interactionController = UIPercentDrivenInteractiveTransition()
            current?.navigationController?.popViewController(animated: true)

        case .changed:
            interactionController?.update(percentComplete)

        case .ended, .cancelled:
            let speed = gesture.velocity(in: gesture.view)
            if speed.x > 0 || (speed.x == 0 && percentComplete > 0.5) {
                interactionController?.finish()
            } else {
                interactionController?.cancel()
            }
            interactionController = nil


        default:
            break
        }
    }
}

和

class CustomNavigationAnimator: NSObject, UIViewControllerAnimatedTransitioning {

    let transitionType: UINavigationController.Operation

    init(transitionType: UINavigationController.Operation) {
        self.transitionType = transitionType
        super.init()
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        let inView   = transitionContext.containerView
        let toView   = transitionContext.view(forKey: .to)!
        let fromView = transitionContext.view(forKey: .from)!

        var frame = inView.bounds

        switch transitionType {
        case .push:
            frame.origin.x = frame.size.width
            toView.frame = frame

            inView.addSubview(toView)
            UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
                toView.frame = inView.bounds
            }, completion: { finished in
                transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
            })

        case .pop:
            toView.frame = frame
            inView.insertSubview(toView, belowSubview: fromView)

            UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
                frame.origin.x = frame.size.width
                fromView.frame = frame
            }, completion: { finished in
                transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
            })

        case .none:
            break
        }
    }

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.5
    }
}

然后，如果第二个 View Controller 想要自定义交互式弹出窗口以及滑动到第三个 View Controller 的能力:

class SecondViewController: UIViewController {

    var navigationDelegate: CustomNavigationDelegate { return navigationController!.delegate as! CustomNavigationDelegate }

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationDelegate.addPushInteractionController(to: view)
        navigationDelegate.addPopInteractionController(to: view)
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        navigationDelegate.pushDestination = { [weak self] in
            self?.storyboard?.instantiateViewController(withIdentifier: "Third")
        }
    }

}

但是如果最后一个 View Controller 不能推送任何东西，只能弹出:

class ThirdViewController: UIViewController {

    var navigationDelegate: CustomNavigationDelegate { return navigationController!.delegate as! CustomNavigationDelegate }

    override func viewDidLoad() {
        super.viewDidLoad()

        navigationDelegate.addPopInteractionController(to: view)
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        navigationDelegate.pushDestination = nil
    }

}