Ios 自定义呈现的UICollectionView&x27的UINavigationController故障;转换期间的内容偏移量
我今天发现了一只奇怪的虫子。这是一张gif。 为了更好的测量,一张清晰地显示它的图像。 如您所见,Ios 自定义呈现的UICollectionView&x27的UINavigationController故障;转换期间的内容偏移量,ios,swift,uinavigationcontroller,uikit,custom-transition,Ios,Swift,Uinavigationcontroller,Uikit,Custom Transition,我今天发现了一只奇怪的虫子。这是一张gif。 为了更好的测量,一张清晰地显示它的图像。 如您所见,topViewController中的UICollectionView在推到下一个视图控制器之前会出现奇怪的起伏偏移行为 我怀疑问题可能在于UINavigationController的自定义表示,它表示我从中推出的水平卡 下面是如何进行的自定义代码。出现故障的视图控制器只是一个普通的navigationController?.pushViewController(viewController,
topViewController
中的UICollectionView
在推到下一个视图控制器之前会出现奇怪的起伏偏移行为
我怀疑问题可能在于UINavigationController
的自定义表示,它表示我从中推出的水平卡
下面是如何进行的自定义代码。出现故障的视图控制器只是一个普通的navigationController?.pushViewController(viewController,动画:true)
从俯视图控制器推送
片段A-演示文稿
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
guard let viewModel = viewModel else { return }
// V This is a UINavigationController
let viewController = viewModel.getViewController(displayingOfferAt: indexPath.item)
viewController.modalPresentationStyle = .custom
viewController.transitioningDelegate = self
present(viewController, animated: true)
}
片段B-正在转换的委托
extension StorefrontViewController: UIViewControllerTransitioningDelegate {
func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
switch presented {
case is CashStore.FullNavigationController:
return CashStore.FullPresentationController(presentedViewController: presented, presenting: presenting)
default:
return nil
}
}
}
片段C-演示控制器
class FullPresentationController: UIPresentationController {
// MARK: Outlets
private lazy var backgroundView: UIView = {
$0.isUserInteractionEnabled = true
$0.backgroundColor = #colorLiteral(red: 0, green: 0, blue: 0, alpha: 0.8016641695)
return $0
}(UIView())
// MARK: Overrides
override func containerViewDidLayoutSubviews() {
super.containerViewDidLayoutSubviews()
presentedView?.frame = frameOfPresentedViewInContainerView
backgroundView.frame = containerView!.bounds
}
override func presentationTransitionWillBegin() {
backgroundView.alpha = 0.0
containerView?.addSubview(backgroundView)
presentedViewController.transitionCoordinator?.animate(alongsideTransition: { context in
self.backgroundView.alpha = 1.0
})
}
override func dismissalTransitionWillBegin() {
presentedViewController.transitionCoordinator?.animate(alongsideTransition: { context in
self.backgroundView.alpha = 0.0
}, completion: { context in
self.backgroundView.removeFromSuperview()
})
}
// MARK: Actions
@objc func dismiss() {
presentingViewController.dismiss(animated: true)
}
}
class FullNavigationController: TiseNavigationController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .clear
}
}
片段D-用于捕捉的自定义集合视图布局
class ProductFlowLayout: UICollectionViewFlowLayout {
override init() {
super.init()
scrollDirection = .horizontal
}
required init?(coder _: NSCoder) {
return nil
}
override func targetContentOffset(forProposedContentOffset proposedContentOffset: CGPoint, withScrollingVelocity velocity: CGPoint) -> CGPoint {
guard let collectionView = collectionView else {
return super.targetContentOffset(forProposedContentOffset: proposedContentOffset, withScrollingVelocity: velocity)
}
var offsetAdjustment = CGFloat.greatestFiniteMagnitude
let horizontalOffset = proposedContentOffset.x + collectionView.contentInset.left
let targetRect = CGRect(x: proposedContentOffset.x, y: 0, width: collectionView.bounds.size.width, height: collectionView.bounds.size.height)
let layoutAttributesArray = super.layoutAttributesForElements(in: targetRect) ?? []
for attributes in layoutAttributesArray where fabsf(Float(attributes.frame.origin.x - horizontalOffset)) < fabsf(Float(offsetAdjustment)) {
offsetAdjustment = attributes.frame.origin.x - horizontalOffset
}
let flowDelegate = collectionView.delegate as? UICollectionViewDelegateFlowLayout
let leftInset = flowDelegate?.collectionView?(collectionView, layout: self, insetForSectionAt: 0).left ?? 0.0
let targetOffset = CGPoint(x: proposedContentOffset.x + offsetAdjustment - leftInset, y: proposedContentOffset.y)
return targetOffset
}
}
类ProductFlowLayout:UICollectionViewFlowLayout{
重写init(){
super.init()
滚动方向=水平方向
}
必需的初始化?(编码器:NSCoder){
归零
}
覆盖func targetContentOffset(forProposedContentOffset proposedContentOffset:CGPoint,使用CrollingVelocity:CGPoint)->CGPoint{
guard let collectionView=collectionView else{
返回super.targetContentOffset(forProposedContentOffset:proposedContentOffset,带CrollingVelocity:velocity)
}
var offsetAdjustment=CGFloat.greatestFiniteMagnitude
设horizontalOffset=proposedContentOffset.x+collectionView.contentInset.left
设targetRect=CGRect(x:proposedContentOffset.x,y:0,宽度:collectionView.bounds.size.width,高度:collectionView.bounds.size.height)
让layoutAttributesArray=super.layoutAttributesForElements(在:targetRect中)??[]
对于布局属性阵列中的属性,其中fabsf(Float(attributes.frame.origin.x-horizontalpoffset))
我已尝试禁用内容偏移调整,但没有改变任何内容。我还尝试在带有卡的视图控制器和集合视图上禁用
maskToBounds
,但没有成功。对不起,问题太长了,我希望有人能帮我解决这个奇怪的问题