Dactyloidae iOS initial commit

mobile/ios/Client/Frontend/Widgets/PhotonActionSheetAnimator.swift

@@ -0,0 +1,79 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import UIKit
+
+class PhotonActionSheetAnimator: NSObject, UIViewControllerAnimatedTransitioning {
+    
+    var presenting: Bool = false
+    let animationDuration = 0.4
+    
+    lazy var shadow: UIView = {
+        let shadow = UIView()
+        shadow.backgroundColor = UIColor(white: 0, alpha: 0.5)
+        return shadow
+    }()
+    
+    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
+        let screens = (from: transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)!, to: transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)!)
+        
+        guard let actionSheet = (self.presenting ? screens.to : screens.from) as? PhotonActionSheet else {
+            return
+        }
+        
+        let bottomViewController = (self.presenting ? screens.from : screens.to) as UIViewController
+        animateWitVC(actionSheet, presentingVC: bottomViewController, transitionContext: transitionContext)
+    }
+    
+    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
+        return animationDuration
+    }
+}
+
+extension PhotonActionSheetAnimator: UIViewControllerTransitioningDelegate {
+    func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
+        self.presenting = true
+        return self
+    }
+    
+    func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
+        self.presenting = false
+        return self
+    }
+}
+
+extension PhotonActionSheetAnimator {
+    fileprivate func animateWitVC(_ actionSheet: PhotonActionSheet, presentingVC viewController: UIViewController, transitionContext: UIViewControllerContextTransitioning) {
+        let containerView = transitionContext.containerView
+        
+        if presenting {
+            shadow.frame = containerView.bounds
+            containerView.addSubview(shadow)
+            actionSheet.view.frame = CGRect(origin: CGPoint(x: 0, y: containerView.frame.size.height), size: containerView.frame.size)
+            self.shadow.alpha = 0
+            containerView.addSubview(actionSheet.view)
+            actionSheet.view.layoutIfNeeded()
+            
+            UIView.animate(withDuration: transitionDuration(using: transitionContext), delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 0.3, options: [], animations: { () -> Void in
+                self.shadow.alpha = 1
+                actionSheet.view.frame = containerView.bounds
+                actionSheet.view.layoutIfNeeded()
+            }, completion: { (completed) -> Void in
+                transitionContext.completeTransition(completed)
+            })
+            
+        } else {
+            UIView.animate(withDuration: transitionDuration(using: transitionContext), delay: 0, usingSpringWithDamping: 1.2, initialSpringVelocity: 0.0, options: [], animations: { () -> Void in
+                self.shadow.alpha = 0
+                actionSheet.view.frame = CGRect(origin: CGPoint(x: 0, y: containerView.frame.size.height), size: containerView.frame.size)
+                actionSheet.view.layoutIfNeeded()
+            }, completion: { (completed) -> Void in
+                actionSheet.view.removeFromSuperview()
+                self.shadow.removeFromSuperview()
+                transitionContext.completeTransition(completed)
+            })
+        }
+    }
+}
+