529 lines
24 KiB
Swift
529 lines
24 KiB
Swift
//
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// MediaHostToMediaPreviewViewControllerAnimatedTransitioning.swift
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// Mastodon
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//
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// Created by MainasuK Cirno on 2021-4-28.
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//
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import os.log
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import UIKit
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import func AVFoundation.AVMakeRect
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final class MediaHostToMediaPreviewViewControllerAnimatedTransitioning: ViewControllerAnimatedTransitioning {
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let transitionItem: MediaPreviewTransitionItem
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let panGestureRecognizer: UIPanGestureRecognizer
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private var isTransitionContextFinish = false
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private var popInteractiveTransitionAnimator = MediaHostToMediaPreviewViewControllerAnimatedTransitioning.animator(initialVelocity: .zero)
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private var itemInteractiveTransitionAnimator = MediaHostToMediaPreviewViewControllerAnimatedTransitioning.animator(initialVelocity: .zero)
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init(operation: UINavigationController.Operation, transitionItem: MediaPreviewTransitionItem, panGestureRecognizer: UIPanGestureRecognizer) {
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self.transitionItem = transitionItem
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self.panGestureRecognizer = panGestureRecognizer
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super.init(operation: operation)
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}
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class func animator(initialVelocity: CGVector = .zero) -> UIViewPropertyAnimator {
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let timingParameters = UISpringTimingParameters(mass: 4.0, stiffness: 1300, damping: 180, initialVelocity: initialVelocity)
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return UIViewPropertyAnimator(duration: 0.5, timingParameters: timingParameters)
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}
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}
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// MARK: - UIViewControllerAnimatedTransitioning
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extension MediaHostToMediaPreviewViewControllerAnimatedTransitioning {
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override func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
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super.animateTransition(using: transitionContext)
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switch operation {
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case .push: pushTransition(using: transitionContext).startAnimation()
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case .pop: popTransition(using: transitionContext).startAnimation()
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default: return
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}
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}
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private func pushTransition(using transitionContext: UIViewControllerContextTransitioning, curve: UIView.AnimationCurve = .easeInOut) -> UIViewPropertyAnimator {
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guard let toVC = transitionContext.viewController(forKey: .to) as? MediaPreviewViewController,
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let toView = transitionContext.view(forKey: .to) else {
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fatalError()
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}
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let toViewEndFrame = transitionContext.finalFrame(for: toVC)
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toView.frame = toViewEndFrame
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toView.alpha = 0
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transitionContext.containerView.addSubview(toView)
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// set to image hidden
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toVC.pagingViewController.view.alpha = 0
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// set from image hidden. update hidden when paging. seealso: `MediaPreviewViewController`
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transitionItem.source.updateAppearance(position: .start, index: toVC.viewModel.currentPage)
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// Set transition image view
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assert(transitionItem.initialFrame != nil)
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let initialFrame = transitionItem.initialFrame ?? toViewEndFrame
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let transitionTargetFrame: CGRect = {
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let aspectRatio = transitionItem.aspectRatio ?? CGSize(width: initialFrame.width, height: initialFrame.height)
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return AVMakeRect(aspectRatio: aspectRatio, insideRect: toView.bounds)
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}()
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let transitionImageView: UIImageView = {
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let imageView = UIImageView(frame: transitionContext.containerView.convert(initialFrame, from: nil))
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imageView.clipsToBounds = true
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imageView.contentMode = .scaleAspectFill
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imageView.isUserInteractionEnabled = false
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imageView.image = transitionItem.image
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// accessibility
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imageView.accessibilityIgnoresInvertColors = true
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return imageView
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}()
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transitionItem.targetFrame = transitionTargetFrame
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transitionItem.transitionView = transitionImageView
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transitionContext.containerView.addSubview(transitionImageView)
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toVC.closeButtonBackground.alpha = 0
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if UIAccessibility.isReduceTransparencyEnabled {
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toVC.visualEffectView.alpha = 0
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}
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let animator = MediaHostToMediaPreviewViewControllerAnimatedTransitioning.animator(initialVelocity: .zero)
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animator.addAnimations {
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transitionImageView.frame = transitionTargetFrame
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toView.alpha = 1
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if UIAccessibility.isReduceTransparencyEnabled {
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toVC.visualEffectView.alpha = 1
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}
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}
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animator.addCompletion { position in
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toVC.pagingViewController.view.alpha = 1
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transitionImageView.removeFromSuperview()
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UIView.animate(withDuration: 0.33, delay: 0, options: [.curveEaseInOut]) {
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toVC.closeButtonBackground.alpha = 1
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}
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transitionContext.completeTransition(position == .end)
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}
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return animator
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}
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@discardableResult
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private func popTransition(
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using transitionContext: UIViewControllerContextTransitioning,
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curve: UIView.AnimationCurve = .easeInOut
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) -> UIViewPropertyAnimator {
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let animator = popInteractiveTransitionAnimator
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animator.addCompletion { position in
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transitionContext.completeTransition(position == .end)
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}
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guard let fromVC = transitionContext.viewController(forKey: .from) as? MediaPreviewViewController,
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let index = fromVC.pagingViewController.currentIndex,
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let fromView = transitionContext.view(forKey: .from),
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let mediaPreviewTransitionViewController = fromVC.pagingViewController.currentViewController as? MediaPreviewTransitionViewController,
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let mediaPreviewTransitionContext = mediaPreviewTransitionViewController.mediaPreviewTransitionContext
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else {
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animator.addAnimations {
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self.transitionItem.source.updateAppearance(position: .end, index: nil)
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}
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return animator
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}
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// update close button
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UIView.animate(withDuration: 0.33, delay: 0, options: [.curveEaseInOut]) {
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fromVC.closeButtonBackground.alpha = 0
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}
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animator.addCompletion { position in
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UIView.animate(withDuration: 0.33, delay: 0, options: [.curveEaseInOut]) {
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fromVC.closeButtonBackground.alpha = position == .end ? 0 : 1
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}
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}
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// update view controller
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fromVC.pagingViewController.isUserInteractionEnabled = false
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animator.addCompletion { position in
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fromVC.pagingViewController.isUserInteractionEnabled = true
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}
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// update background
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let blurEffect = fromVC.visualEffectView.effect
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animator.addAnimations {
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fromVC.visualEffectView.effect = nil
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if UIAccessibility.isReduceTransparencyEnabled {
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fromVC.visualEffectView.alpha = 0
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}
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}
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animator.addCompletion { position in
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fromVC.visualEffectView.effect = position == .end ? nil : blurEffect
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if UIAccessibility.isReduceTransparencyEnabled {
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fromVC.visualEffectView.alpha = position == .end ? 0 : 1
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}
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}
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// update transition item source
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animator.addCompletion { position in
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if position == .end {
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// reset appearance
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self.transitionItem.source.updateAppearance(position: position, index: nil)
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}
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}
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// update transitioning snapshot
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let transitionMaskView = UIView(frame: transitionContext.containerView.bounds)
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transitionMaskView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
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transitionContext.containerView.addSubview(transitionMaskView)
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transitionItem.interactiveTransitionMaskView = transitionMaskView
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animator.addCompletion { position in
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transitionMaskView.removeFromSuperview()
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}
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let transitionMaskViewTapGestureRecognizer = UITapGestureRecognizer.singleTapGestureRecognizer
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transitionMaskViewTapGestureRecognizer.addTarget(self, action: #selector(MediaHostToMediaPreviewViewControllerAnimatedTransitioning.transitionMaskViewTapGestureRecognizerHandler(_:)))
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transitionMaskView.addGestureRecognizer(transitionMaskViewTapGestureRecognizer)
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let maskLayer = CAShapeLayer()
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maskLayer.frame = transitionMaskView.bounds
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maskLayer.path = UIBezierPath(rect: maskLayer.bounds).cgPath
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transitionMaskView.layer.mask = maskLayer
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transitionItem.interactiveTransitionMaskLayer = maskLayer
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// attach transitioning snapshot
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mediaPreviewTransitionContext.snapshot.center = transitionMaskView.center
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mediaPreviewTransitionContext.snapshot.contentMode = .scaleAspectFill
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mediaPreviewTransitionContext.snapshot.clipsToBounds = true
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transitionMaskView.addSubview(mediaPreviewTransitionContext.snapshot)
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fromVC.view.bringSubviewToFront(fromVC.closeButtonBackground)
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transitionItem.transitionView = mediaPreviewTransitionContext.transitionView
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transitionItem.snapshotTransitioning = mediaPreviewTransitionContext.snapshot
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transitionItem.initialFrame = mediaPreviewTransitionContext.snapshot.frame
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// assert view hierarchy not change
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let toVC = transitionItem.previewableViewController
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let targetFrame = toVC.sourceFrame(transitionItem: transitionItem, index: index)
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transitionItem.targetFrame = targetFrame
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animator.addAnimations {
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self.transitionItem.snapshotTransitioning?.layer.cornerRadius = self.transitionItem.sourceImageViewCornerRadius ?? 0
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}
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animator.addCompletion { position in
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self.transitionItem.snapshotTransitioning?.layer.cornerRadius = position == .end ? 0 : (self.transitionItem.sourceImageViewCornerRadius ?? 0)
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}
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if !isInteractive {
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animator.addAnimations {
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if let targetFrame = targetFrame {
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self.transitionItem.snapshotTransitioning?.frame = targetFrame
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} else {
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fromView.alpha = 0
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}
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}
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// calculate transition mask
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let maskLayerToRect: CGRect? = {
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guard case .attachments = transitionItem.source else { return nil }
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guard let navigationBar = toVC.navigationController?.navigationBar, let navigationBarSuperView = navigationBar.superview else { return nil }
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let navigationBarFrameInWindow = navigationBarSuperView.convert(navigationBar.frame, to: nil)
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// crop rect top edge
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var rect = transitionMaskView.frame
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let _toViewFrameInWindow = toVC.view.superview.flatMap { $0.convert(toVC.view.frame, to: nil) }
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if let toViewFrameInWindow = _toViewFrameInWindow, toViewFrameInWindow.minY > navigationBarFrameInWindow.maxY {
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rect.origin.y = toViewFrameInWindow.minY
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} else {
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rect.origin.y = navigationBarFrameInWindow.maxY + UIView.separatorLineHeight(of: toVC.view) // extra hairline
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}
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return rect
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}()
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let maskLayerToPath = maskLayerToRect.flatMap { UIBezierPath(rect: $0) }?.cgPath
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let maskLayerToFinalRect: CGRect? = {
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guard case .attachments = transitionItem.source else { return nil }
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var rect = maskLayerToRect ?? transitionMaskView.frame
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// clip tabBar when bar visible
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guard let tabBarController = toVC.tabBarController,
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!tabBarController.tabBar.isHidden,
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let tabBarSuperView = tabBarController.tabBar.superview
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else { return rect }
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let tabBarFrameInWindow = tabBarSuperView.convert(tabBarController.tabBar.frame, to: nil)
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let offset = rect.maxY - tabBarFrameInWindow.minY
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guard offset > 0 else { return rect }
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rect.size.height -= offset
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return rect
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}()
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// FIXME:
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let maskLayerToFinalPath = maskLayerToFinalRect.flatMap { UIBezierPath(rect: $0) }?.cgPath
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if let maskLayerToPath = maskLayerToPath {
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maskLayer.path = maskLayerToPath
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}
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}
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mediaPreviewTransitionContext.transitionView.isHidden = true
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animator.addCompletion { position in
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self.transitionItem.transitionView?.isHidden = position == .end
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self.transitionItem.snapshotRaw?.alpha = position == .start ? 1.0 : 0.0
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self.transitionItem.snapshotTransitioning?.removeFromSuperview()
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}
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return animator
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}
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}
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// MARK: - UIViewControllerInteractiveTransitioning
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extension MediaHostToMediaPreviewViewControllerAnimatedTransitioning {
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override func startInteractiveTransition(_ transitionContext: UIViewControllerContextTransitioning) {
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super.startInteractiveTransition(transitionContext)
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switch operation {
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case .pop:
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// Note: change item.imageView transform via pan gesture
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panGestureRecognizer.addTarget(self, action: #selector(MediaHostToMediaPreviewViewControllerAnimatedTransitioning.updatePanGestureInteractive(_:)))
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popInteractiveTransition(using: transitionContext)
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default:
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assertionFailure()
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return
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}
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}
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private func popInteractiveTransition(using transitionContext: UIViewControllerContextTransitioning) {
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popTransition(using: transitionContext)
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}
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}
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extension MediaHostToMediaPreviewViewControllerAnimatedTransitioning {
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// app may freeze without response during transitioning
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// patch it by tap the view to finish transitioning
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@objc func transitionMaskViewTapGestureRecognizerHandler(_ sender: UITapGestureRecognizer) {
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// not panning now but still in transitioning
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guard panGestureRecognizer.state == .possible,
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transitionContext.isAnimated, transitionContext.isInteractive else {
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return
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}
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// finish or cancel current transitioning
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let targetPosition = completionPosition()
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os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: target position: %s", ((#file as NSString).lastPathComponent), #line, #function, targetPosition == .end ? "end" : "start")
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isTransitionContextFinish = true
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animate(targetPosition)
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targetPosition == .end ? transitionContext.finishInteractiveTransition() : transitionContext.cancelInteractiveTransition()
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}
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@objc func updatePanGestureInteractive(_ sender: UIPanGestureRecognizer) {
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guard !isTransitionContextFinish else {
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return
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} // do not accept transition abort
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switch sender.state {
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case .possible:
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return
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case .began, .changed:
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let translation = sender.translation(in: transitionContext.containerView)
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let percent = popInteractiveTransitionAnimator.fractionComplete + progressStep(for: translation)
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popInteractiveTransitionAnimator.fractionComplete = percent
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transitionContext.updateInteractiveTransition(percent)
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updateTransitionItemPosition(of: translation)
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// Reset translation to zero
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sender.setTranslation(CGPoint.zero, in: transitionContext.containerView)
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case .ended, .cancelled:
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let targetPosition = completionPosition()
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os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: target position: %s", ((#file as NSString).lastPathComponent), #line, #function, targetPosition == .end ? "end" : "start")
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isTransitionContextFinish = true
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animate(targetPosition)
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targetPosition == .end ? transitionContext.finishInteractiveTransition() : transitionContext.cancelInteractiveTransition()
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case .failed:
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return
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@unknown default:
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assertionFailure()
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return
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}
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}
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private func convert(_ velocity: CGPoint, for item: MediaPreviewTransitionItem?) -> CGVector {
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guard let currentFrame = item?.transitionView?.frame,
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let targetFrame = item?.targetFrame
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else {
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return CGVector.zero
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}
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let dx = abs(targetFrame.midX - currentFrame.midX)
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let dy = abs(targetFrame.midY - currentFrame.midY)
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guard dx > 0.0 && dy > 0.0 else {
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return CGVector.zero
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}
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let range = CGFloat(35.0)
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let clippedVx = clip(-range, range, velocity.x / dx)
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let clippedVy = clip(-range, range, velocity.y / dy)
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return CGVector(dx: clippedVx, dy: clippedVy)
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}
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private func completionPosition() -> UIViewAnimatingPosition {
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let completionThreshold: CGFloat = 0.33
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let flickMagnitude: CGFloat = 1200 // pts/sec
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let velocity = panGestureRecognizer.velocity(in: transitionContext.containerView).vector
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let isFlick = (velocity.magnitude > flickMagnitude)
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let isFlickDown = isFlick && (velocity.dy > 0.0)
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let isFlickUp = isFlick && (velocity.dy < 0.0)
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if (operation == .push && isFlickUp) || (operation == .pop && isFlickDown) {
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return .end
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} else if (operation == .push && isFlickDown) || (operation == .pop && isFlickUp) {
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return .start
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} else if popInteractiveTransitionAnimator.fractionComplete > completionThreshold {
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return .end
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} else {
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return .start
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}
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}
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// Create item animator and start it
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func animate(_ toPosition: UIViewAnimatingPosition) {
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// Create a property animator to animate each image's frame change
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let gestureVelocity = panGestureRecognizer.velocity(in: transitionContext.containerView)
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let velocity = convert(gestureVelocity, for: transitionItem)
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let itemAnimator = MediaHostToMediaPreviewViewControllerAnimatedTransitioning.animator(initialVelocity: velocity)
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var maskLayerToFinalPath: CGPath?
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if toPosition == .end,
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let transitionMaskView = transitionItem.interactiveTransitionMaskView,
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let snapshot = transitionItem.snapshotTransitioning {
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let toVC = transitionItem.previewableViewController
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var needsMaskWithAnimation = true
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let maskLayerToRect: CGRect? = {
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guard case .attachments = transitionItem.source else { return nil }
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guard let navigationBar = toVC.navigationController?.navigationBar, let navigationBarSuperView = navigationBar.superview else { return nil }
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let navigationBarFrameInWindow = navigationBarSuperView.convert(navigationBar.frame, to: nil)
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// crop rect top edge
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var rect = transitionMaskView.frame
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let _toViewFrameInWindow = toVC.view.superview.flatMap { $0.convert(toVC.view.frame, to: nil) }
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if let toViewFrameInWindow = _toViewFrameInWindow, toViewFrameInWindow.minY > navigationBarFrameInWindow.maxY {
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rect.origin.y = toViewFrameInWindow.minY
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} else {
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rect.origin.y = navigationBarFrameInWindow.maxY + UIView.separatorLineHeight(of: toVC.view) // extra hairline
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}
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if rect.minY < snapshot.frame.minY {
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needsMaskWithAnimation = false
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}
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return rect
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}()
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let maskLayerToPath = maskLayerToRect.flatMap { UIBezierPath(rect: $0) }?.cgPath
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if let maskLayer = transitionItem.interactiveTransitionMaskLayer, !needsMaskWithAnimation {
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maskLayer.path = maskLayerToPath
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}
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let maskLayerToFinalRect: CGRect? = {
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guard case .attachments = transitionItem.source else { return nil }
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var rect = maskLayerToRect ?? transitionMaskView.frame
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// clip rect bottom when tabBar visible
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guard let tabBarController = toVC.tabBarController,
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!tabBarController.tabBar.isHidden,
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let tabBarSuperView = tabBarController.tabBar.superview
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else { return rect }
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let tabBarFrameInWindow = tabBarSuperView.convert(tabBarController.tabBar.frame, to: nil)
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let offset = rect.maxY - tabBarFrameInWindow.minY
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guard offset > 0 else { return rect }
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rect.size.height -= offset
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return rect
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}()
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maskLayerToFinalPath = maskLayerToFinalRect.flatMap { UIBezierPath(rect: $0) }?.cgPath
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}
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itemAnimator.addAnimations {
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if let maskLayer = self.transitionItem.interactiveTransitionMaskLayer,
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let maskLayerToFinalPath = maskLayerToFinalPath {
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maskLayer.path = maskLayerToFinalPath
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}
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if toPosition == .end {
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switch self.transitionItem.source {
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case .profileBanner where toPosition == .end:
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// fade transition for banner
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self.transitionItem.snapshotTransitioning?.alpha = 0
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default:
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if let targetFrame = self.transitionItem.targetFrame {
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self.transitionItem.snapshotTransitioning?.frame = targetFrame
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} else {
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self.transitionItem.snapshotTransitioning?.alpha = 0
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}
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}
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} else {
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if let initialFrame = self.transitionItem.initialFrame {
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self.transitionItem.snapshotTransitioning?.frame = initialFrame
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} else {
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self.transitionItem.snapshotTransitioning?.alpha = 1
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}
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}
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}
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// Start the property animator and keep track of it
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self.itemInteractiveTransitionAnimator = itemAnimator
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itemAnimator.startAnimation()
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// Reverse the transition animator if we are returning to the start position
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popInteractiveTransitionAnimator.isReversed = (toPosition == .start)
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if popInteractiveTransitionAnimator.state == .inactive {
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popInteractiveTransitionAnimator.startAnimation()
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|
} else {
|
|
let durationFactor = CGFloat(itemAnimator.duration / popInteractiveTransitionAnimator.duration)
|
|
popInteractiveTransitionAnimator.continueAnimation(withTimingParameters: nil, durationFactor: durationFactor)
|
|
}
|
|
}
|
|
|
|
private func progressStep(for translation: CGPoint) -> CGFloat {
|
|
return (operation == .push ? -1.0 : 1.0) * translation.y / transitionContext.containerView.bounds.midY
|
|
}
|
|
|
|
private func updateTransitionItemPosition(of translation: CGPoint) {
|
|
let progress = progressStep(for: translation)
|
|
|
|
let initialSize = transitionItem.initialFrame!.size
|
|
guard initialSize != .zero else { return }
|
|
// assert(initialSize != .zero)
|
|
|
|
guard let snapshot = transitionItem.snapshotTransitioning,
|
|
let finalSize = transitionItem.targetFrame?.size else {
|
|
return
|
|
}
|
|
|
|
if snapshot.frame.size == .zero {
|
|
snapshot.frame.size = initialSize
|
|
}
|
|
|
|
let currentSize = snapshot.frame.size
|
|
|
|
let itemPercentComplete = clip(-0.05, 1.05, (currentSize.width - initialSize.width) / (finalSize.width - initialSize.width) + progress)
|
|
let itemWidth = lerp(initialSize.width, finalSize.width, itemPercentComplete)
|
|
let itemHeight = lerp(initialSize.height, finalSize.height, itemPercentComplete)
|
|
assert(currentSize.width != 0.0)
|
|
assert(currentSize.height != 0.0)
|
|
let scaleTransform = CGAffineTransform(scaleX: (itemWidth / currentSize.width), y: (itemHeight / currentSize.height))
|
|
let scaledOffset = transitionItem.touchOffset.apply(transform: scaleTransform)
|
|
|
|
snapshot.center = (snapshot.center + (translation + (transitionItem.touchOffset - scaledOffset))).point
|
|
snapshot.bounds = CGRect(origin: CGPoint.zero, size: CGSize(width: itemWidth, height: itemHeight))
|
|
transitionItem.touchOffset = scaledOffset
|
|
}
|
|
|
|
}
|
|
|