UIViewControllerAnimatedTransitioning 每隔一段时间才有效吗？

Posted 2023-03-14

【中文标题】UIViewControllerAnimatedTransitioning 每隔一段时间才有效吗？

【英文标题】：UIViewControllerAnimatedTransitioning only works every other time?

【发布时间】：2017-08-29 17:36:35

【问题描述】：

我已经在这几个小时了，无法理解我做错了什么。我已经按照我之前的Swift: Problems with custom UIView.transition? 中描述的UITabBarControllerDelegate 装配了自定义标签栏控制器转换

我不使用普通的故事板标签栏按钮，我以编程方式切换 selectedIndex。我的问题是，只有实现了这个：

func tabBarController(_ tabBarController: UITabBarController, animationControllerForTransitionFrom fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? 
        let animator = ModalTransition()
        animator.fromView = fromVC.view
        animator.toView = toVC.view
        return  animator

    

索引的动画和切换仅每隔一次发生一次。我有自定义按钮来切换索引，每隔一段时间，当我单击切换按钮时没有任何反应。这是我的动画：

//
//  ModalTransition.swift
//  Adventures In Design
//
//  Created by Skylar Thomas on 8/28/17.
//

import UIKit

class ModalTransition: NSObject, UIViewControllerAnimatedTransitioning 

    weak var transitionContext: UIViewControllerContextTransitioning?
    var fromView = UIView()
    var toView = UIView()
    var duration = 1.1


    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval 
        return 1
    

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) 

        let containerView = transitionContext.containerView
        containerView.addSubview(toView)
        containerView.sendSubview(toBack: toView)

        print("ANIMATING")

        UIView.animate(withDuration: duration, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.0, options: .curveLinear, animations: 
            self.fromView.center.y += 900

        , completion: 
            finished in

            //only works every OTHER click
            transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
            self.fromView.center.y -= 900
        )


    

这是什么原因造成的？是什么东西吗

【参考方案1】：

我认为你没有分配你的 toView 和 FromView。试试这样的

func animateTransition(using transitionContext: UIViewControllerContextTransitioning) 

    let fromViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)!
    let toViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)!

    let fromView = fromViewController.view
    let toView = toViewController.view
    let container = transitionContext.containerView
    container.addSubview(toView!)

    // Replace your animations here
    toView?.frame = transitionContext.finalFrame(for: toViewController)
    toView?.alpha = 0

    let duration = self.transitionDuration(using: transitionContext)

    UIView.animate(withDuration: duration, delay: 0, options: .curveEaseInOut, animations: 
      toView?.alpha = 1
      fromView?.alpha = 0

    , completion:  finished in

      toView?.alpha = 1.0
      fromView?.alpha = 1
      fromView?.removeFromSuperview()
      transitionContext.completeTransition(true)
    )
  

【讨论】：

仍然只适用于其他所有。你能展示一个动画例子吗？也许我的动画不正确

当然..检查编辑的答案。让我知道是否有帮助

里面的东西修复了它。谢谢！