Question

我希望有一个奇怪的UINavigationController概念，您可以通过平移（如iOS 7流行手势）将视图控制器从堆栈中弹出，但它会记住弹出的视图控制器，允许你通过平移另一个方向来“取消它”（将其推回到堆栈上）。可以把它想象成Safari中的前进和后退按钮，如果你想回去，你仍然可以继续前进，然后把页面带回来。

我已经将UINavigationController子类化，并将自己设置为委托，返回UIViewControllerAnimatedTransitioning对象和UIPercentDrivenInteractiveTransition对象：

func navigationController(navigationController: UINavigationController, animationControllerForOperation operation: UINavigationControllerOperation, fromViewController fromVC: UIViewController, toViewController toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
    if operation == .Push {
        return Animator(presenting: true)
    } else if operation == .Pop {
        return Animator(presenting: false)
    } else {
        return nil
    }
}

和

func navigationController(navigationController: UINavigationController, interactionControllerForAnimationController animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
    if animationController is Animator {
        return interactiveTransition
    } else {
        return nil
    }
}

根据Animator是否设置呈现，我会调用特定的方法，如果呈现的是真的：

func presentWithTransitionContext(transitionContext: UIViewControllerContextTransitioning) {
    let toViewControllerView = transitionContext.viewControllerForKey(UITransitionContextToViewControllerKey)!.view
    let containerView = transitionContext.containerView()

    containerView.addSubview(toViewControllerView)
    toViewControllerView.transform = CGAffineTransformMakeTranslation(containerView.bounds.width, 0.0)
    applyShadowToView(toViewControllerView)

    let animationCurve: UIViewAnimationOptions = transitionContext.isInteractive() ? .CurveLinear : .CurveEaseInOut

    UIView.animateWithDuration(transitionDuration(transitionContext), delay: 0.0, options: animationCurve, animations: {
        toViewControllerView.transform = CGAffineTransformIdentity
    }, completion: { finished in
        return transitionContext.completeTransition(!transitionContext.transitionWasCancelled())
    })
}

我覆盖popViewControllerAnimated，因此我可以保存正在弹出的视图控制器：

override func popViewControllerAnimated(animated: Bool) -> UIViewController? {
    poppedViewControllers.insert(visibleViewController!, atIndex: 0)
    return super.popViewControllerAnimated(animated)
}

我在UIPanGestureRecognizer子类'UINavigationController中添加awakeFromNib()到它的视图，并调用此方法来推送/弹出：

func panned(panGestureRecognizer: UIPanGestureRecognizer) {
    let panningRight = panGestureRecognizer.translationInView(view).x > 0
    let progress: CGFloat

    if panningRight {
        progress = panGestureRecognizer.translationInView(view).x / view.bounds.width
    } else {
        progress = -panGestureRecognizer.translationInView(view).x / view.bounds.width
    }

    if panGestureRecognizer.state == .Began {
        interactiveTransition = UIPercentDrivenInteractiveTransition()

        if panningRight {
            popViewControllerAnimated(true)
        } else {
            let viewControllerToPush = poppedViewControllers[0]
            poppedViewControllers.removeAtIndex(0)
            pushViewController(viewControllerToPush, animated: true)
        }
    } else if panGestureRecognizer.state == .Changed {
        interactiveTransition!.updateInteractiveTransition(progress)
    } else if panGestureRecognizer.state == .Ended {
        if progress > 0.5 {
            interactiveTransition!.finishInteractiveTransition()
        } else {
            interactiveTransition!.cancelInteractiveTransition()
        }

        interactiveTransition = nil
    } else if panGestureRecognizer.state == .Cancelled {
        interactiveTransition!.cancelInteractiveTransition()
        interactiveTransition = nil
    }
}

然而，每当我手势将先前弹出的视图控制器推到导航堆栈上时，它就会以相反的方式为演示文稿设置动画（显示的视图控制器立即显示，并且当前视图控制器滑开）。我不知道为什么会这样。两种情况都不可能吗？我不应该删除视图吗？

如何进行可以弹出或推送的交互式UINavigationController转换？推动动画正在翻转？

0 个答案: