Swift 3中的自定义转换无法正确转换

Question

我已经实现了一个导航控制器,以结合旋转盘类型的布局(想象每个VC布局成一个圆圈,整体旋转,顺序进入视图.导航控制器配置为使用自定义过渡类,如下所示: -

import UIKit

class RotaryTransition: NSObject, UIViewControllerAnimatedTransitioning {
    let isPresenting :Bool
    let duration :TimeInterval = 0.5
    let animationDuration: TimeInterval = 0.7
    let delay: TimeInterval = 0
    let damping: CGFloat = 1.4
    let spring: CGFloat = 6.0

    init(isPresenting: Bool) {
        self.isPresenting = isPresenting
        super.init()
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        //Get references to the view hierarchy
        let fromViewController: UIViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)!
        let toViewController: UIViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)!
        let sourceRect: CGRect = transitionContext.initialFrame(for: fromViewController)
        let containerView: UIView = transitionContext.containerView

        if self.isPresenting { // Push
            //1. Settings for the fromVC ............................
//            fromViewController.view.frame = sourceRect
            fromViewController.view.layer.anchorPoint = CGPoint(x: 0.5, y: 3);
            fromViewController.view.layer.position = CGPoint(x: fromViewController.view.frame.size.width/2, y: fromViewController.view.frame.size.height * 3);

            //2. Setup toVC view...........................
            containerView.insertSubview(toViewController.view, belowSubview:fromViewController.view)
            toViewController.view.layer.anchorPoint = CGPoint(x: 0.5, y: 3);
            toViewController.view.layer.position = CGPoint(x: toViewController.view.frame.size.width/2, y: toViewController.view.frame.size.height * 3);
            toViewController.view.transform = CGAffineTransform(rotationAngle: 15 * CGFloat(M_PI / 180));

            //3. Perform the animation...............................
            UIView.animate(withDuration: animationDuration, delay:delay, usingSpringWithDamping: damping, initialSpringVelocity: spring, options: [], animations: {
                fromViewController.view.transform = CGAffineTransform(rotationAngle: -15 * CGFloat(M_PI / 180));
                toViewController.view.transform = CGAffineTransform(rotationAngle: 0);
            }, completion: {
                (animated: Bool) -> () in transitionContext.completeTransition(true)
            })
        } else { // Pop
            //1. Settings for the fromVC ............................
            fromViewController.view.frame = sourceRect
            fromViewController.view.layer.anchorPoint = CGPoint(x: 0.5, y: 3);
            fromViewController.view.layer.position = CGPoint(x: fromViewController.view.frame.size.width/2, y: fromViewController.view.frame.size.height * 3);

            //2. Setup toVC view...........................
//            toViewController.view.frame = transitionContext.finalFrame(for: toViewController)
            toViewController.view.layer.anchorPoint = CGPoint(x: 0.5, y: 3);
            toViewController.view.layer.position = CGPoint(x: toViewController.view.frame.size.width/2, y: toViewController.view.frame.size.height * 3);
            toViewController.view.transform = CGAffineTransform(rotationAngle: -15 * CGFloat(M_PI / 180));
            containerView.insertSubview(toViewController.view, belowSubview:fromViewController.view)

            //3. Perform the animation...............................
            UIView.animate(withDuration: animationDuration, delay:delay, usingSpringWithDamping: damping, initialSpringVelocity: spring, options: [], animations: {
                fromViewController.view.transform = CGAffineTransform(rotationAngle: 15 * CGFloat(M_PI / 180));
                toViewController.view.transform = CGAffineTransform(rotationAngle: 0);
            }, completion: {
                //When the animation is completed call completeTransition
                (animated: Bool) -> () in transitionContext.completeTransition(true)
            })            
        }
    }

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

下图中显示了视图如何移动的表示......两个红色区域是问题,如后面所述.

呈现(推)翻译工作正常 - 2移动到1和3移动到2.然而,解雇(弹出)翻译没有,从而解雇VC看似正确地移出视图(2移动到3),但呈现(上一篇)VC到达错误的地方,或者框架尺寸不正确......

对于类按原样,平移导致2移动到3(正确)但是1然后移动到4,视图的大小正确,但似乎偏离预期位置看似任意的距离.此后我尝试了各种不同的解决方案.

在pop部分,我尝试添加以下行(在代码中注释): -

toViewController.view.frame = transitionContext.finalFrame(for: toViewController)

......但VC现在最终收缩(1移至5).我希望有人能看到我正在犯的可能是愚蠢的错误.我试过简单地将推送部分复制到弹出部分(并反转一切),但它只是不起作用!

仅供参考...那些需要知道如何将过渡连接到UINavigationController的人 - 将UINavigationControllerDelegate添加到导航控制器,以及以下功能......

    func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        let transition: SwingTransition = SwingTransition.init(isPresenting: ( operation == .push ? true : false ))
        return transition;
    }

下图显示了所有视图如何共享相同的起始点(用于转换).目的是给出一个左轮手枪枪管的幻觉,将每个VC移动到视野中.顶部中心视图表示查看窗口,显示堆栈中的第三个视图.为可怜的视觉效果道歉......

Answer 1

问题是恢复的视图控制器视图中的某个属性未正确重置.我建议在动画完成时重置它(你可能不想保持非标准transform,anchorPoint如果你以后做其他动画,假设视图没有被转换).所以,在completion动画的块,重设position,anchorPoint和transform的看法.

class RotaryTransition: NSObject, UIViewControllerAnimatedTransitioning {
    let isPresenting: Bool
    let duration: TimeInterval = 0.5
    let delay: TimeInterval = 0
    let damping: CGFloat = 1.4
    let spring: CGFloat = 6

    init(isPresenting: Bool) {
        self.isPresenting = isPresenting
        super.init()
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        let from   = transitionContext.viewController(forKey: .from)!
        let to     = transitionContext.viewController(forKey: .to)!
        let frame  = transitionContext.initialFrame(for: from)
        let height = frame.size.height
        let width  = frame.size.width

        let angle: CGFloat = 15.0 * .pi / 180.0
        let rotationCenterOffset: CGFloat = width / 2 / tan(angle / 2) / height + 1  // use fixed value, e.g. 3, if you want, or use this to ensure that the corners of the two views just touch, but don't overlap

        let rightTransform  = CATransform3DMakeRotation(angle, 0, 0, 1)
        let leftTransform   = CATransform3DMakeRotation(-angle, 0, 0, 1)

        transitionContext.containerView.insertSubview(to.view, aboveSubview: from.view)

        // save the anchor and position

        let anchorPoint = from.view.layer.anchorPoint
        let position    = from.view.layer.position

        // prepare `to` layer for rotation

        to.view.layer.anchorPoint = CGPoint(x: 0.5, y: rotationCenterOffset)
        to.view.layer.position = CGPoint(x: width / 2, y: height * rotationCenterOffset)
        to.view.layer.transform = self.isPresenting ? rightTransform : leftTransform
        //to.view.layer.opacity = 0

        // prepare `from` layer for rotation

        from.view.layer.anchorPoint = CGPoint(x: 0.5, y: rotationCenterOffset)
        from.view.layer.position = CGPoint(x: width / 2, y: height * rotationCenterOffset)

        // rotate

        UIView.animate(withDuration: duration, delay: delay, usingSpringWithDamping: damping, initialSpringVelocity: spring, animations: {
            from.view.layer.transform = self.isPresenting ? leftTransform : rightTransform
            to.view.layer.transform = CATransform3DIdentity
            //to.view.layer.opacity = 1
            //from.view.layer.opacity = 0
        }, completion: { finished in
            // restore the layers to their default configuration

            for view in [to.view, from.view] {
                view?.layer.transform = CATransform3DIdentity
                view?.layer.anchorPoint = anchorPoint
                view?.layer.position = position
                //view?.layer.opacity = 1
            }

            transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
        })
    }

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

当我在这里时,我做了一些其他的改变:

• 消除了分号;
• 消除了其中一个持续时间属性;
• 修复了方法completion闭包参数的名称,而不是更准确地反映它的真正目的是什么......你也可以使用;animatefinishedanimated_
• 设置completeTransition基于动画是否被取消或没有(因为如果你做这种互动/取消,你不想总是使用true);
• 使用.pi而不是M_PI;
• 我评论了我的调整opacity,但我通常这样做是为了让效果更加润滑,并确保如果你调整角度使视图重叠,你就不会像动画开始那样得到其他视图的任何奇怪的瑕疵或者就像它的完成; 我实际上已经计算了参数,所以没有重叠,无论屏幕尺寸如何,所以这没有必要,我注释掉了这些opacity线条,但你可以考虑使用它们,具体取决于所需的效果.

之前我展示了如何简化过程,但结果效果并不完全符合您的要求,但如果您有兴趣,请参阅此答案的上一个演绎.