我有一个自定义动画，除了在关闭动画结束时会出现黑屏外，其他方面都正常。
过渡的代码如下：
class FolderAnimationController: NSObject, UIViewControllerAnimatedTransitioning {
let duration = 5.0
var presenting = true
var originFrame = CGRect.zero
var selectedFolderCell: FolderCollectionViewCell?
func transitionDuration(_ transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return duration
}
func animateTransition(_ transitionContext: UIViewControllerContextTransitioning) {
let containerView = transitionContext.containerView()
let toViewC = transitionContext.viewController(forKey: UITransitionContextToViewControllerKey)!
let fromViewC = transitionContext.viewController(forKey: UITransitionContextFromViewControllerKey)!
let folderViewC = presenting ? fromViewC as! ViewController : transitionContext.viewController(forKey: UITransitionContextToViewControllerKey) as! ViewController
let projectViewC = presenting ? toViewC as! ProjectViewController : transitionContext.viewController(forKey: UITransitionContextFromViewControllerKey) as! ProjectViewController
let cellView = presenting ? (folderViewC.folderCollectionView.cellForItem(at: (folderViewC.folderCollectionView.indexPathsForSelectedItems()?.first!)!) as! FolderCollectionViewCell).folderView : projectViewC.containerView
let cellSnapshot: UIView = presenting ? cellView!.snapshotView(afterScreenUpdates: false)! : cellView!.snapshotView(afterScreenUpdates: false)!
let cellFrame = containerView.convert(cellView!.frame, from: cellView!.superview)
cellSnapshot.frame = cellFrame
cellView!.isHidden = true
toViewC.view.frame = transitionContext.finalFrame(for: toViewC)
toViewC.view.layoutIfNeeded()
toViewC.view.alpha = 0
presenting ? (projectViewC.containerView.isHidden = true) : (self.selectedFolderCell!.folderView.isHidden = true)
containerView.addSubview(toViewC.view)
containerView.addSubview(cellSnapshot)
UIView.animate(withDuration: duration, animations: {
toViewC.view.alpha = 1.0
let finalFrame = self.presenting ? projectViewC.containerView.frame : self.originFrame
cellSnapshot.frame = finalFrame
}) { (_) in
self.presenting ? (projectViewC.containerView.isHidden = false) : (self.selectedFolderCell?.isHidden = false)
cellSnapshot.removeFromSuperview()
transitionContext.completeTransition(true)
}
}
}
以下是调用动画的第一个视图控制器的代码：
func animationController(forPresentedController presented: UIViewController, presenting: UIViewController, sourceController source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
presentAnimator.presenting = true
presentAnimator.originFrame = openingFrame!
presentAnimator.selectedFolderCell = selectedCell!
return presentAnimator
}
func animationController(forDismissedController dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
presentAnimator.presenting = false
return presentAnimator
}