Web app improvements

submodules/AttachmentUI/Sources/AttachmentContainer.swift

@@ -144,8 +144,11 @@ final class AttachmentContainer: ASDisplayNode, UIGestureRecognizerDelegate {
         return false
     }
     
+    var isTracking: Bool {
+        return self.panGestureArguments != nil
+    }
+    
     private var panGestureArguments: (topInset: CGFloat, offset: CGFloat, scrollView: UIScrollView?, listNode: ListView?)?
-
     @objc func panGesture(_ recognizer: UIPanGestureRecognizer) {
         guard let (layout, controllers, coveredByModalTransition) = self.validLayout else {
             return

submodules/AttachmentUI/Sources/AttachmentController.swift

@@ -18,6 +18,7 @@ public enum AttachmentButtonType: Equatable {
     case contact
     case poll
     case app(PeerId, String, TelegramMediaFile)
+    case standalone
 }
 
 public protocol AttachmentContainable: ViewController {
@@ -25,6 +26,7 @@ public protocol AttachmentContainable: ViewController {
     var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void { get set }
     var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void { get set }
     var cancelPanGesture: () -> Void { get set }
+    var isContainerPanning: () -> Bool { get set }
     
     func resetForReuse()
     func prepareForReuse()
@@ -349,6 +351,15 @@ public class AttachmentController: ViewController {
                                 strongSelf.container.cancelPanGesture()
                             }
                         }
+                        
+                        controller.isContainerPanning = { [weak self] in
+                            if let strongSelf = self {
+                                return strongSelf.container.isTracking
+                            } else {
+                                return false
+                            }
+                        }
+                        
                         let previousController = strongSelf.currentControllers.last
                         strongSelf.currentControllers = [controller]
                         
@@ -557,14 +568,21 @@ public class AttachmentController: ViewController {
                 containerTransition.updateFrame(node: self.container, frame: CGRect(origin: CGPoint(), size: containerRect.size))
                 
                 var containerInsets = containerLayout.intrinsicInsets
-                containerInsets.bottom = panelHeight
+                var hasPanel = false
+                if let controller = self.controller, controller.buttons.count > 1 {
+                    hasPanel = true
+                    containerInsets.bottom = panelHeight
+                }
+
                 let containerLayout = containerLayout.withUpdatedIntrinsicInsets(containerInsets)
                 
                 self.container.update(layout: containerLayout, controllers: controllers, coveredByModalTransition: 0.0, transition: self.switchingController ? .immediate : transition)
                                     
                 if self.container.supernode == nil, !controllers.isEmpty && self.container.isReady {
                     self.wrapperNode.addSubnode(self.container)
-                    self.container.addSubnode(self.panel)
+                    if hasPanel {
+                        self.container.addSubnode(self.panel)
+                    }
                     
                     self.animateIn()
                 }

submodules/AttachmentUI/Sources/AttachmentPanel.swift

@@ -184,6 +184,10 @@ private final class AttachButtonComponent: CombinedComponent {
                 name = appName
                 imageName = ""
                 imageFile = appIcon
+            case .standalone:
+                name = ""
+                imageName = ""
+                imageFile = nil
             }
             
             let tintColor = component.isSelected ? component.theme.rootController.tabBar.selectedIconColor : component.theme.rootController.tabBar.iconColor

submodules/ComposePollUI/Sources/CreatePollController.swift

@@ -521,6 +521,7 @@ private class CreatePollControllerImpl: ItemListController, AttachmentContainabl
     public var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     public var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void = { _, _ in }
     public var cancelPanGesture: () -> Void = { }
+    public var isContainerPanning: () -> Bool = { return false }
 }
 
 public func createPollController(context: AccountContext, updatedPresentationData: (initial: PresentationData, signal: Signal<PresentationData, NoError>)? = nil, peer: EnginePeer, isQuiz: Bool? = nil, completion: @escaping (ComposedPoll) -> Void) -> AttachmentContainable {

submodules/LegacyUI/Sources/LegacyController.swift

@@ -409,6 +409,7 @@ open class LegacyController: ViewController, PresentableController, AttachmentCo
     open var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     open var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void = { _, _ in }
     open var cancelPanGesture: () -> Void = { }
+    open var isContainerPanning: () -> Bool = { return false }
     
     public init(presentation: LegacyControllerPresentation, theme: PresentationTheme? = nil, strings: PresentationStrings? = nil, initialLayout: ContainerViewLayout? = nil) {
         self.sizeClass.set(SSignal.single(UIUserInterfaceSizeClass.compact.rawValue as NSNumber))

submodules/LocationUI/Sources/LocationPickerController.swift

@@ -75,6 +75,7 @@ public final class LocationPickerController: ViewController, AttachmentContainab
     public var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     public var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void = { _, _ in }
     public var cancelPanGesture: () -> Void = { }
+    public var isContainerPanning: () -> Bool = { return false }
     
     public init(context: AccountContext, updatedPresentationData: (initial: PresentationData, signal: Signal<PresentationData, NoError>)? = nil, mode: LocationPickerMode, completion: @escaping (TelegramMediaMap, String?) -> Void) {
         self.context = context

submodules/MediaPickerUI/Sources/MediaPickerScreen.swift

@@ -133,6 +133,7 @@ public final class MediaPickerScreen: ViewController, AttachmentContainable {
     public var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     public var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void  = { _, _ in }
     public var cancelPanGesture: () -> Void = { }
+    public var isContainerPanning: () -> Bool = { return false }
     
     var dismissAll: () -> Void = { }
     

submodules/TelegramApi/Sources/Api0.swift

@@ -804,7 +804,7 @@ fileprivate let parsers: [Int32 : (BufferReader) -> Any?] = {
     dict[-440534818] = { return Api.Update.parse_updateUserStatus($0) }
     dict[-1071741569] = { return Api.Update.parse_updateUserTyping($0) }
     dict[2139689491] = { return Api.Update.parse_updateWebPage($0) }
-    dict[-118080598] = { return Api.Update.parse_updateWebViewResultSent($0) }
+    dict[361936797] = { return Api.Update.parse_updateWebViewResultSent($0) }
     dict[2027216577] = { return Api.Updates.parse_updateShort($0) }
     dict[1299050149] = { return Api.Updates.parse_updateShortChatMessage($0) }
     dict[826001400] = { return Api.Updates.parse_updateShortMessage($0) }

submodules/TelegramApi/Sources/Api19.swift

@@ -605,7 +605,7 @@ public extension Api {
         case updateUserStatus(userId: Int64, status: Api.UserStatus)
         case updateUserTyping(userId: Int64, action: Api.SendMessageAction)
         case updateWebPage(webpage: Api.WebPage, pts: Int32, ptsCount: Int32)
-        case updateWebViewResultSent(peer: Api.Peer, botId: Int64, queryId: Int64)
+        case updateWebViewResultSent(queryId: Int64)
     
     public func serialize(_ buffer: Buffer, _ boxed: Swift.Bool) {
     switch self {
@@ -1473,12 +1473,10 @@ public extension Api {
                     serializeInt32(pts, buffer: buffer, boxed: false)
                     serializeInt32(ptsCount, buffer: buffer, boxed: false)
                     break
-                case .updateWebViewResultSent(let peer, let botId, let queryId):
+                case .updateWebViewResultSent(let queryId):
                     if boxed {
-                        buffer.appendInt32(-118080598)
+                        buffer.appendInt32(361936797)
                     }
-                    peer.serialize(buffer, true)
-                    serializeInt64(botId, buffer: buffer, boxed: false)
                     serializeInt64(queryId, buffer: buffer, boxed: false)
                     break
     }
@@ -1684,8 +1682,8 @@ public extension Api {
                 return ("updateUserTyping", [("userId", String(describing: userId)), ("action", String(describing: action))])
                 case .updateWebPage(let webpage, let pts, let ptsCount):
                 return ("updateWebPage", [("webpage", String(describing: webpage)), ("pts", String(describing: pts)), ("ptsCount", String(describing: ptsCount))])
-                case .updateWebViewResultSent(let peer, let botId, let queryId):
+                case .updateWebViewResultSent(let queryId):
-                return ("updateWebViewResultSent", [("peer", String(describing: peer)), ("botId", String(describing: botId)), ("queryId", String(describing: queryId))])
+                return ("updateWebViewResultSent", [("queryId", String(describing: queryId))])
     }
     }
     
@@ -3449,19 +3447,11 @@ public extension Api {
             }
         }
         public static func parse_updateWebViewResultSent(_ reader: BufferReader) -> Update? {
-            var _1: Api.Peer?
+            var _1: Int64?
-            if let signature = reader.readInt32() {
+            _1 = reader.readInt64()
-                _1 = Api.parse(reader, signature: signature) as? Api.Peer
-            }
-            var _2: Int64?
-            _2 = reader.readInt64()
-            var _3: Int64?
-            _3 = reader.readInt64()
             let _c1 = _1 != nil
-            let _c2 = _2 != nil
+            if _c1 {
-            let _c3 = _3 != nil
+                return Api.Update.updateWebViewResultSent(queryId: _1!)
-            if _c1 && _c2 && _c3 {
-                return Api.Update.updateWebViewResultSent(peer: _1!, botId: _2!, queryId: _3!)
             }
             else {
                 return nil

submodules/TelegramCore/Sources/State/AccountStateManagementUtils.swift

@@ -1514,7 +1514,7 @@ private func finalStateWithUpdatesAndServerTime(postbox: Postbox, network: Netwo
                 updatedState.updateMessageReactions(MessageId(peerId: peer.peerId, namespace: Namespaces.Message.Cloud, id: msgId), reactions: reactions, eventTimestamp: updatesDate)
             case .updateAttachMenuBots:
                 updatedState.addUpdateAttachMenuBots()
-            case let .updateWebViewResultSent(_, _, queryId):
+            case let .updateWebViewResultSent(queryId):
                 updatedState.addDismissWebView(queryId)
             default:
                 break

submodules/TelegramUI/Sources/AttachmentFileController.swift

@@ -168,6 +168,7 @@ private class AttachmentFileControllerImpl: ItemListController, AttachmentContai
     public var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     public var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void = { _, _ in }
     public var cancelPanGesture: () -> Void = { }
+    public var isContainerPanning: () -> Bool = { return false }
     
     var delayDisappear = false
     

submodules/TelegramUI/Sources/ChatController.swift

@@ -3359,12 +3359,14 @@ public final class ChatControllerImpl: TelegramBaseController, ChatController, G
                     guard let strongSelf = self else {
                         return
                     }
-                    let controller = WebAppController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, peerId: peerId, botId: peerId, botName: botName, url: url, queryId: nil, buttonText: buttonText, keepAliveSignal: nil, replyToMessageId: nil, iconFile: nil)
+                    
-                    controller.getNavigationController = { [weak self] in
+                    let controller = standaloneWebAppController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, peerId: peerId, botId: peerId, botName: botName, url: url, queryId: nil, buttonText: buttonText, keepAliveSignal: nil)
-                        return self?.effectiveNavigationController
+                    strongSelf.present(controller, in: .window(.root))
-                    }
+//                    controller.getNavigationController = { [weak self] in
-                    controller.navigationPresentation = .modal
+//                        return self?.effectiveNavigationController
-                    strongSelf.push(controller)
+//                    }
+//                    controller.navigationPresentation = .modal
+//                    strongSelf.push(controller)
                 }, error: { [weak self] error in
                     if let strongSelf = self {
                         strongSelf.present(textAlertController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, title: nil, text: strongSelf.presentationData.strings.Login_UnknownError, actions: [TextAlertAction(type: .defaultAction, title: strongSelf.presentationData.strings.Common_OK, action: {
@@ -3380,12 +3382,14 @@ public final class ChatControllerImpl: TelegramBaseController, ChatController, G
                     guard let strongSelf = self else {
                         return
                     }
-                    let controller = WebAppController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, peerId: peerId, botId: peerId, botName: botName, url: result.url, queryId: result.queryId, buttonText: buttonText, keepAliveSignal: result.keepAliveSignal, replyToMessageId: nil, iconFile: nil)
+                    let controller = standaloneWebAppController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, peerId: peerId, botId: peerId, botName: botName, url: url, queryId: result.queryId, buttonText: buttonText, keepAliveSignal: result.keepAliveSignal)
-                    controller.getNavigationController = { [weak self] in
+                    strongSelf.present(controller, in: .window(.root))
-                        return self?.effectiveNavigationController
+//                    let controller = WebAppController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, peerId: peerId, botId: peerId, botName: botName, url: result.url, queryId: result.queryId, buttonText: buttonText, keepAliveSignal: result.keepAliveSignal, replyToMessageId: nil, iconFile: nil)
-                    }
+//                    controller.getNavigationController = { [weak self] in
-                    controller.navigationPresentation = .modal
+//                        return self?.effectiveNavigationController
-                    strongSelf.push(controller)
+//                    }
+//                    controller.navigationPresentation = .modal
+//                    strongSelf.push(controller)
                 }, error: { [weak self] error in
                     if let strongSelf = self {
                         strongSelf.present(textAlertController(context: strongSelf.context, updatedPresentationData: strongSelf.updatedPresentationData, title: nil, text: strongSelf.presentationData.strings.Login_UnknownError, actions: [TextAlertAction(type: .defaultAction, title: strongSelf.presentationData.strings.Common_OK, action: {
@@ -10870,6 +10874,8 @@ public final class ChatControllerImpl: TelegramBaseController, ChatController, G
                     }
                     completion(controller, nil)
                     strongSelf.controllerNavigationDisposable.set(nil)
+                default:
+                    break
                 }
             }
             let present = {

submodules/TelegramUI/Sources/ContactSelectionController.swift

@@ -79,6 +79,7 @@ class ContactSelectionControllerImpl: ViewController, ContactSelectionController
     var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void = { _, _ in }
     var cancelPanGesture: () -> Void = { }
+    var isContainerPanning: () -> Bool = { return false }
     
     init(_ params: ContactSelectionControllerParams) {
         self.context = params.context

submodules/WebUI/Sources/WebAppController.swift

@@ -113,11 +113,12 @@ public final class WebAppController: ViewController, AttachmentContainable {
     public var updateNavigationStack: (@escaping ([AttachmentContainable]) -> ([AttachmentContainable], AttachmentMediaPickerContext?)) -> Void = { _ in }
     public var updateTabBarAlpha: (CGFloat, ContainedViewLayoutTransition) -> Void  = { _, _ in }
     public var cancelPanGesture: () -> Void = { }
+    public var isContainerPanning: () -> Bool = { return false }
     
     private class Node: ViewControllerTracingNode, WKNavigationDelegate, UIScrollViewDelegate {
         private weak var controller: WebAppController?
         
-        fileprivate var webView: WKWebView?
+        fileprivate var webView: WebAppWebView?
         
         private var placeholderIcon: UIImage?
         private var placeholderNode: ShimmerEffectNode?
@@ -183,7 +184,7 @@ public final class WebAppController: ViewController, AttachmentContainable {
                 configuration.mediaPlaybackRequiresUserAction = false
             }
             
-            let webView = WKWebView(frame: CGRect(), configuration: configuration)
+            let webView = WebAppWebView(frame: CGRect(), configuration: configuration)
             webView.alpha = 0.0
             webView.isOpaque = false
             webView.backgroundColor = .clear
@@ -200,6 +201,7 @@ public final class WebAppController: ViewController, AttachmentContainable {
             }
             webView.allowsBackForwardNavigationGestures = false
             webView.scrollView.delegate = self
+            webView.scrollView.contentInset = UIEdgeInsets(top: 0.0, left: 0.0, bottom: 1.0, right: 0.0)
             webView.addObserver(self, forKeyPath: #keyPath(WKWebView.estimatedProgress), options: [], context: nil)
             webView.tintColor = self.presentationData.theme.rootController.tabBar.iconColor
             self.webView = webView
@@ -335,39 +337,16 @@ public final class WebAppController: ViewController, AttachmentContainable {
         }
         
         private var animationProgress: CGFloat = 0.0
+        private var floatSnapshotView: UIView?
+        
+        
+        
+        
         func containerLayoutUpdated(_ layout: ContainerViewLayout, navigationBarHeight: CGFloat, transition: ContainedViewLayoutTransition) {
-            if let webView = self.webView {
+            if let webView = self.webView, let controller = self.controller {
                 let frame = CGRect(origin: CGPoint(x: layout.safeInsets.left, y: navigationBarHeight), size: CGSize(width: layout.size.width - layout.safeInsets.left - layout.safeInsets.right, height: max(1.0, layout.size.height - navigationBarHeight - layout.intrinsicInsets.bottom - layout.additionalInsets.bottom)))
-                if case let .animated(duration, curve) = transition, let springAnimation = transition.animation(), webView.frame != frame {
+                
-                    let initial = webView.frame
+                webView.updateFrame(frame: frame, panning: controller.isContainerPanning(), transition: transition)
-                        
-                    let animation = POPBasicAnimation()
-                    animation.property = (POPAnimatableProperty.property(withName: "frame", initializer: { property in
-                        property?.readBlock = { node, values in
-                            values?.pointee = (node as! Node).animationProgress
-                        }
-                        property?.writeBlock = { node, values in
-                            (node as! Node).animationProgress = values!.pointee
-                            var mappedValue = values!.pointee
-                            switch curve {
-                                case .spring:
-                                    mappedValue = springAnimationValueAt(springAnimation, mappedValue)
-                                default:
-                                break
-                            }
-                            let currentFrame = CGRect.interpolator()(initial, frame, mappedValue) as! CGRect
-                            (node as! Node).webView?.frame = currentFrame
-                        }
-                        property?.threshold = 0.01
-                    }) as! POPAnimatableProperty)
-                    animation.fromValue = 0.0 as NSNumber
-                    animation.toValue = 1.0 as NSNumber
-                    animation.timingFunction = CAMediaTimingFunction(name: CAMediaTimingFunctionName.linear)
-                    animation.duration = duration * Double(springAnimation.speed)
-                    self.pop_add(animation, forKey: "frame")
-                } else {
-                    webView.frame = frame
-                }
             }
             
             if let placeholderNode = self.placeholderNode {
@@ -671,3 +650,11 @@ private final class WebAppContextReferenceContentSource: ContextReferenceContent
         return ContextControllerReferenceViewInfo(referenceView: self.sourceNode.view, contentAreaInScreenSpace: UIScreen.main.bounds)
     }
 }
+
+public func standaloneWebAppController(context: AccountContext, updatedPresentationData: (initial: PresentationData, signal: Signal<PresentationData, NoError>)? = nil, peerId: PeerId, botId: PeerId, botName: String, url: String, queryId: Int64?, buttonText: String?, keepAliveSignal: Signal<Never, KeepWebViewError>?) -> ViewController {
+    let controller = AttachmentController(context: context, updatedPresentationData: updatedPresentationData, chatLocation: .peer(id: peerId), buttons: [.standalone], initialButton: .standalone)
+    controller.requestController = { _, completion in
+        completion(WebAppController(context: context, updatedPresentationData: updatedPresentationData, peerId: peerId, botId: botId, botName: botName, url: url, queryId: queryId, buttonText: buttonText, keepAliveSignal: keepAliveSignal, replyToMessageId: nil, iconFile: nil), nil)
+    }
+    return controller
+}

submodules/WebUI/Sources/WebAppWebView.swift

@@ -0,0 +1,135 @@
+import Foundation
+import UIKit
+import Display
+import WebKit
+import SwiftSignalKit
+
+private let findFixedPositionClasses = """
+function findFixedPositionClasses() {
+    var elems = document.body.getElementsByTagName("*");
+    var len = elems.length
+
+    var result = []
+    var j = 0;
+    for (var i = 0; i < len; i++) {
+        if ((window.getComputedStyle(elems[i],null).getPropertyValue('position') == 'fixed') && (window.getComputedStyle(elems[i],null).getPropertyValue('bottom') == '0px')) {
+            result[j] = elems[i].className;
+            j++;
+        }
+    }
+    return result;
+}
+findFixedPositionClasses();
+"""
+
+private func findFixedPositionViews(webView: WKWebView, classes: [String]) -> [(String, UIView)] {
+    if let contentView = webView.scrollView.subviews.first {
+        func recursiveSearch(_ view: UIView) -> [(String, UIView)] {
+            var result: [(String, UIView)] = []
+            
+            let description = view.description
+            if description.contains("class='") {
+                for className in classes {
+                    if description.contains(className) {
+                        result.append((className, view))
+                        break
+                    }
+                }
+            }
+            
+            for subview in view.subviews {
+                result.append(contentsOf: recursiveSearch(subview))
+            }
+            
+            return result
+        }
+        
+        return recursiveSearch(contentView)
+    } else {
+        return []
+    }
+}
+
+final class WebAppWebView: WKWebView {
+    private var fixedPositionClasses: [String] = []
+    private var currentFixedViews: [(String, UIView, UIView)] = []
+    
+    private var timer: SwiftSignalKit.Timer?
+    
+    deinit {
+        self.timer?.invalidate()
+    }
+    
+    override func didMoveToSuperview() {
+        super.didMoveToSuperview()
+        
+        if self.timer == nil {
+            let timer = SwiftSignalKit.Timer(timeout: 1.0, repeat: true, completion: { [weak self] in
+                guard let strongSelf = self else {
+                    return
+                }
+                
+                strongSelf.evaluateJavaScript(findFixedPositionClasses, completionHandler: { [weak self] result, _ in
+                    if let result = result {
+                        Queue.mainQueue().async {
+                            self?.fixedPositionClasses = (result as? [String]) ?? []
+                        }
+                    }
+                })
+            }, queue: Queue.mainQueue())
+            timer.start()
+            self.timer = timer
+        }
+    }
+    
+    
+    
+    func updateFrame(frame: CGRect, panning: Bool, transition: ContainedViewLayoutTransition) {
+        if panning {
+            let fixedPositionViews = findFixedPositionViews(webView: self, classes: self.fixedPositionClasses)
+            if fixedPositionViews.count != self.currentFixedViews.count {
+                for (_, view, snapshotView) in self.currentFixedViews {
+                    view.alpha = 1.0
+                    snapshotView.removeFromSuperview()
+                }
+                self.currentFixedViews = []
+                
+                var updatedFixedViews: [(String, UIView, UIView)] = []
+                for (className, view) in fixedPositionViews {
+                    if let snapshotView = view.snapshotView(afterScreenUpdates: false) {
+                        updatedFixedViews.append((className, view, snapshotView))
+                        self.addSubview(snapshotView)
+                    }
+                }
+                self.currentFixedViews = updatedFixedViews
+            }
+            
+            transition.updateFrame(view: self, frame: frame)
+            
+            for (_, view, snapshotView) in self.currentFixedViews {
+                view.alpha = 0.0
+                
+                var snapshotFrame = view.frame
+                snapshotFrame.origin.y = frame.height - snapshotFrame.height
+                transition.updateFrame(view: snapshotView, frame: snapshotFrame)
+            }
+        } else {
+            for (_, view, snapshotView) in self.currentFixedViews {
+                view.alpha = 0.0
+                
+                var snapshotFrame = view.frame
+                snapshotFrame.origin.y = frame.height - snapshotFrame.height
+                transition.updateFrame(view: snapshotView, frame: snapshotFrame)
+            }
+            
+            transition.updateFrame(view: self, frame: frame, completion: { _ in
+                for (_, view, snapshotView) in self.currentFixedViews {
+                    view.alpha = 1.0
+                    snapshotView.removeFromSuperview()
+                }
+                self.currentFixedViews = []
+            })
+        }
+        
+    }
+}