ios - 用过渡呈现 viewController

Question

当我实例化并呈现一个 View Controller 时是否可以定义一种转换类型？

此代码生成默认的淡入淡出类型过渡，但我需要它从左到右出现，这可能吗？

谢谢!

@IBAction func botonVolverFamilias(_ sender: Any) {
    let sw  = revealViewController()
    self.view.window?.rootViewController = sw
    let viewControllerModelos = storyboard!.instantiateViewController(withIdentifier: "vc_catalogo_familias") as! VC_catalogo
    let navigationController = UINavigationController(rootViewController: viewControllerModelos)
    navigationController.navigationBar.isHidden=false
    navigationController.setNavigationBarHidden(true, animated: false)
    sw!.setFront(navigationController, animated: true)
}

Answer 1

要更改 UINavigationController 的转换，您需要使用的是找到堆栈中的第一个 UIViewController。您应该将此 UIViewController 扩展为 UIViewControllerTransitioningDelegate 和 UINavigationControllerDelegate。

然后你可以调用 func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationController.Operation, fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? 来定义什么样的过渡想要呈现新的 UIViewControllers。

因此，为了做到这一点，我们必须创建一个自定义的 UIViewControllerAnimatedTransitioning 类，并在此 UIViewControllerTransitioningDelegate 方法中返回它。这是我使用的示例。

import UIKit

class SimpleOver: NSObject, UIViewControllerAnimatedTransitioning {
    var direction: TransitionDirection!

    init(direction: TransitionDirection) {
        self.direction = direction
    }


    var popStyle: Bool = false

    func transitionDuration(
    using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.20
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {

        if popStyle {

            animatePop(using: transitionContext)
            return
        }

        let fz = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)!
        let tz = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)!

        let f = transitionContext.finalFrame(for: tz)

        let fOff = f.offsetBy(dx: f.width, dy: 0)
        tz.view.frame = fOff

        transitionContext.containerView.insertSubview(tz.view, aboveSubview: fz.view)

        UIView.animate(
        withDuration: transitionDuration(using: transitionContext),
        animations: {
                tz.view.frame = f
                for subview in fz.view.subviews {
                    subview.alpha = 0
                }
        }, completion: {_ in
            transitionContext.completeTransition(true)
        })
    }

    func animatePop(using transitionContext: UIViewControllerContextTransitioning) {

        let fz = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)!
        let tz = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)!

        let f = transitionContext.initialFrame(for: fz)
        let fOffPop = f.offsetBy(dx: f.width, dy: 0)

        transitionContext.containerView.insertSubview(tz.view, belowSubview: fz.view)

        UIView.animate(
        withDuration: transitionDuration(using: transitionContext),
        animations: {
                fz.view.frame = fOffPop
                for subview in tz.view.subviews {
                    subview.alpha = 1
                }
        }, completion: {_ in
            transitionContext.completeTransition(true)
        })
    }
}

enum TransitionDirection {
    case left
    case right
}

然后，在我们的 func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationController.Operation, fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? 方法中，我们可以简单地返回这个UIViewControllerAnimatedTransitioning 如下:

extension YourViewController: UIViewControllerTransitioningDelegate, UINavigationControllerDelegate {
    func navigationController(
    _ navigationController: UINavigationController,
    animationControllerFor operation: UINavigationController.Operation,
    from fromVC: UIViewController,
    to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {

        //This tells our navigation controller the style that we want to animate our transition between view controllers

        let simpleOver = SimpleOver(direction: .right)
        simpleOver.popStyle = (operation == .pop)
        return simpleOver
    }
}