Question

我正在开发一款使用导航控制器的应用。我有一个特定的视图控制器，在导航栏中有一个左右按钮，每个按钮都会切换到一个不同的视图控制器。当我按下右键时，我只需拨打self.performSegue(withIdentifier: "ToDestination", sender: nil)，当我弹回时，我会拨打_ = self.navigationController?.popViewController(animated: true)。

我的问题是当我按下左按钮时。我可以推送和弹出，但我希望过渡与右按钮相反。由于我按下左键，我希望segue从左向右过渡，当我弹出时，我希望segue从右向左过渡。

我可以按照我想要的方式使转换工作：

//push
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc = storyboard.instantiateViewController(withIdentifier: "SearchController") as! SearchController
let transition: CATransition = CATransition()
let timeFunc : CAMediaTimingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
transition.duration = 0.5
transition.timingFunction = timeFunc
transition.type = kCATransitionPush
transition.subtype = kCATransitionFromLeft
self.navigationController!.view.layer.add(transition, forKey: kCATransition)
self.navigationController!.pushViewController(vc, animated: true)

//pop
let transition: CATransition = CATransition()
let timeFunc : CAMediaTimingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
transition.duration = 0.5
transition.timingFunction = timeFunc
transition.type = kCATransitionPush
transition.subtype = kCATransitionFromRight
self.navigationController!.view.layer.add(transition, forKey: kCATransition)
_ = self.navigationController?.popViewController(animated: true)

这样可行，但在视图控制器之间转换时会出现黑色闪烁。有没有更好的方法来获得默认的过渡动画？

Answer 1

实现这一目标的最佳方法是通过符合UIViewControllerAnimatedTransitioning协议来创建自定义推送和流行动画： -

//CustomPushAnimation class

import UIKit

class CustomPushAnimation: NSObject, UIViewControllerAnimatedTransitioning {

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.2
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        let containerVw = transitionContext.containerView
        let fromViewController = transitionContext.viewController(forKey: .from)
        let toViewController = transitionContext.viewController(forKey: .to)
        guard let fromVc = fromViewController, let toVc = toViewController else { return }
        let finalFrame = transitionContext.finalFrame(for: toVc)
        //Below line will start from left
        toVc.view.frame = finalFrame.offsetBy(dx: -finalFrame.size.width/2, dy: 0)
        containerVw.addSubview(toVc.view)
        UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
            toVc.view.frame = finalFrame
            fromVc.view.alpha = 0.5
        }, completion: {(finished) in
            transitionContext.completeTransition(finished)
            fromVc.view.alpha = 1.0
        })
    }
}



//CustomPopAnimation class
import UIKit

class CustomPopAnimation: NSObject, UIViewControllerAnimatedTransitioning {
    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.2
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        let containerView = transitionContext.containerView
        let fromViewController = transitionContext.viewController(forKey: .from)
        let toViewController = transitionContext.viewController(forKey: .to)
        guard let fromVc = fromViewController,
            let toVc = toViewController,
            let snapshotView = fromVc.view.snapshotView(afterScreenUpdates: false)
            else { return }
        let finalFrame = transitionContext.finalFrame(for: fromVc)
        toVc.view.frame = finalFrame
        containerView.addSubview(toVc.view)
        containerView.sendSubview(toBack: toVc.view)
        snapshotView.frame = fromVc.view.frame
        containerView.addSubview(snapshotView)
        fromVc.view.removeFromSuperview()
        UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
            //Below line will start from right
            snapshotView.frame = finalFrame.offsetBy(dx: -finalFrame.size.width, dy: 0)
        }, completion: {(finished) in
            snapshotView.removeFromSuperview()
            transitionContext.completeTransition(finished)
        })
    }
}

最后你需要使用设置呈现新的View控制器动画标志为true，否则无法正常工作

//Below code should be inside YourViewController
    let vc = UIStoryboard(name: "storyboardName", bundle: nil).instantiateViewController(withIdentifier: "ViewControllerIdentifier")            let navigationController = BaseNavigationController(rootViewController: vc)
    navigationController.transitioningDelegate = self
    present(navigationController, animated: true, completion: nil)

您还需要符合UIViewControllerTransitioningDelegate 协议，以便工作动画

  extension YourViewController: UIViewControllerTransitioningDelegate {
    func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
            return customPushAnimation
        }

    func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
            return customPopAnimation
        }
    }

自定义segue过渡动画

1 个答案: