Create MainWindow folder to match Mac folder structure.

iOS/MainWindow/Article/ImageTransition.swift

@@ -0,0 +1,110 @@
+//
+//  ImageAnimator.swift
+//  NetNewsWire-iOS
+//
+//  Created by Maurice Parker on 10/15/19.
+//  Copyright © 2019 Ranchero Software. All rights reserved.
+//
+
+import UIKit
+
+final class ImageTransition: NSObject, UIViewControllerAnimatedTransitioning {
+
+	private weak var webViewController: WebViewController?
+	private let duration = 0.4
+	var presenting = true
+	var originFrame: CGRect!
+	var maskFrame: CGRect!
+	var originImage: UIImage!
+
+	init(controller: WebViewController) {
+		self.webViewController = controller
+	}
+
+	func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
+		return duration
+	}
+
+	func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+		if presenting {
+			animateTransitionPresenting(using: transitionContext)
+		} else {
+			animateTransitionReturning(using: transitionContext)
+		}
+	}
+
+	private func animateTransitionPresenting(using transitionContext: UIViewControllerContextTransitioning) {
+
+		let imageView = UIImageView(image: originImage)
+		imageView.frame = originFrame
+
+		let fromView = transitionContext.view(forKey: .from)!
+		fromView.removeFromSuperview()
+
+		transitionContext.containerView.backgroundColor = AppColor.fullScreenBackground
+		transitionContext.containerView.addSubview(imageView)
+
+		webViewController?.hideClickedImage()
+
+		UIView.animate(
+			withDuration: duration,
+			delay: 0.0,
+			usingSpringWithDamping: 0.8,
+			initialSpringVelocity: 0.2,
+			animations: {
+				let imageController = transitionContext.viewController(forKey: .to) as! ImageViewController
+				imageView.frame = imageController.zoomedFrame
+			}, completion: { _ in
+				imageView.removeFromSuperview()
+				let toView = transitionContext.view(forKey: .to)!
+				transitionContext.containerView.addSubview(toView)
+				transitionContext.completeTransition(true)
+		})
+	}
+
+	private func animateTransitionReturning(using transitionContext: UIViewControllerContextTransitioning) {
+		let imageController = transitionContext.viewController(forKey: .from) as! ImageViewController
+		let imageView = UIImageView(image: originImage)
+		imageView.frame = imageController.zoomedFrame
+
+		let fromView = transitionContext.view(forKey: .from)!
+		let windowFrame = fromView.window!.frame
+		fromView.removeFromSuperview()
+
+		let toView = transitionContext.view(forKey: .to)!
+		transitionContext.containerView.addSubview(toView)
+
+		let maskingView = UIView()
+
+		let fullMaskFrame = CGRect(x: windowFrame.minX, y: maskFrame.minY, width: windowFrame.width, height: maskFrame.height)
+        let path = UIBezierPath(rect: fullMaskFrame)
+        let maskLayer = CAShapeLayer()
+		maskLayer.path = path.cgPath
+		maskingView.layer.mask = maskLayer
+
+		maskingView.addSubview(imageView)
+		transitionContext.containerView.addSubview(maskingView)
+
+		UIView.animate(
+			withDuration: duration,
+			delay: 0.0,
+			usingSpringWithDamping: 0.8,
+			initialSpringVelocity: 0.2,
+			animations: {
+				imageView.frame = self.originFrame
+			}, completion: { _ in
+				if let controller = self.webViewController {
+					controller.showClickedImage {
+						DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
+							imageView.removeFromSuperview()
+							transitionContext.completeTransition(true)
+						}
+					}
+				} else {
+					imageView.removeFromSuperview()
+					transitionContext.completeTransition(true)
+				}
+		})
+	}
+
+}