Rework the presentation of the media browser quick look view to use SwiftUI.

ElementX/Sources/FlowCoordinators/MediaEventsTimelineFlowCoordinator.swift

@@ -95,8 +95,8 @@ class MediaEventsTimelineFlowCoordinator: FlowCoordinatorProtocol {
         coordinator.actions
             .sink { [weak self] action in
                 switch action {
-                case .viewInRoomTimeline(let itemID):
-                    self?.actionsSubject.send(.viewInRoomTimeline(itemID))
+                case .viewItem(let previewContext):
+                    self?.presentMediaPreview(for: previewContext)
                 }
             }
             .store(in: &cancellables)
@@ -105,4 +105,26 @@ class MediaEventsTimelineFlowCoordinator: FlowCoordinatorProtocol {
             self?.actionsSubject.send(.finished)
         }
     }
+
+    private func presentMediaPreview(for previewContext: TimelineMediaPreviewContext) {
+        let parameters = TimelineMediaPreviewCoordinatorParameters(context: previewContext,
+                                                                   mediaProvider: userSession.mediaProvider,
+                                                                   userIndicatorController: userIndicatorController)
+
+        let coordinator = TimelineMediaPreviewCoordinator(parameters: parameters)
+        coordinator.actionsPublisher
+            .sink { [weak self] action in
+                switch action {
+                case .viewInRoomTimeline(let itemID):
+                    self?.navigationStackCoordinator.pop(animated: false)
+                    self?.actionsSubject.send(.viewInRoomTimeline(itemID))
+                    self?.navigationStackCoordinator.setFullScreenCoverCoordinator(nil)
+                case .dismiss:
+                    self?.navigationStackCoordinator.setFullScreenCoverCoordinator(nil)
+                }
+            }
+            .store(in: &cancellables)
+
+        navigationStackCoordinator.setFullScreenCoverCoordinator(coordinator)
+    }
 }

ElementX/Sources/FlowCoordinators/RoomFlowCoordinator.swift

@@ -1581,8 +1581,8 @@ class RoomFlowCoordinator: FlowCoordinatorProtocol {
                     MXLog.error("Unable to present room timeline for event \(itemID)")
                     return
                 }
-                stateMachine.tryEvent(.dismissMediaEventsTimeline)
-                stateMachine.tryEvent(.presentRoom(presentationAction: .eventFocus(.init(eventID: eventID, shouldSetPin: false))))
+                stateMachine.tryEvent(.presentRoom(presentationAction: .eventFocus(.init(eventID: eventID, shouldSetPin: false))),
+                                      userInfo: EventUserInfo(animated: false)) // No animation so the timeline visible when the preview animates away.
             case .finished:
                 stateMachine.tryEvent(.dismissMediaEventsTimeline)
             }

ElementX/Sources/Other/Extensions/PlatformViewVersionPredicate.swift

@@ -10,18 +10,24 @@ import SwiftUIIntrospect
 
 extension PlatformViewVersionPredicate<TextFieldType, UITextField> {
     static var supportedVersions: Self {
-        .iOS(.v16, .v17, .v18)
+        .iOS(.v17, .v18)
     }
 }
 
 extension PlatformViewVersionPredicate<ScrollViewType, UIScrollView> {
     static var supportedVersions: Self {
-        .iOS(.v16, .v17, .v18)
+        .iOS(.v17, .v18)
     }
 }
 
 extension PlatformViewVersionPredicate<ViewControllerType, UIViewController> {
     static var supportedVersions: Self {
-        .iOS(.v16, .v17, .v18)
+        .iOS(.v17, .v18)
+    }
+}
+
+extension PlatformViewVersionPredicate<NavigationStackType, UINavigationController> {
+    static var supportedVersions: Self {
+        .iOS(.v17, .v18)
     }
 }

ElementX/Sources/Other/SwiftUI/Animation/ZoomTransition.swift

@@ -0,0 +1,30 @@
+//
+// Copyright 2024 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+//
+
+import SwiftUI
+
+extension View {
+    /// A convenience modifier to conditionally apply `.navigationTransition(.zoom(…))` when available.
+    @ViewBuilder
+    func zoomTransition(sourceID: some Hashable, in namespace: Namespace.ID) -> some View {
+        if #available(iOS 18.0, *) {
+            navigationTransition(.zoom(sourceID: sourceID, in: namespace))
+        } else {
+            self
+        }
+    }
+
+    /// A convenience modifier to conditionally apply `.matchedTransitionSource(…)` when available.
+    @ViewBuilder
+    func zoomTransitionSource(id: some Hashable, in namespace: Namespace.ID) -> some View {
+        if #available(iOS 18.0, *) {
+            matchedTransitionSource(id: id, in: namespace)
+        } else {
+            self
+        }
+    }
+}

ElementX/Sources/Other/SwiftUI/Views/BlurEffectView.swift

@@ -0,0 +1,22 @@
+//
+// Copyright 2024 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+//
+
+import SwiftUI
+
+/// A view that renders a `UIBlurEffect` as there is a larger range of
+/// effects available compared to using SwiftUI's `Material` type.
+struct BlurEffectView: UIViewRepresentable {
+    var style: UIBlurEffect.Style
+
+    func makeUIView(context: Context) -> UIVisualEffectView {
+        UIVisualEffectView(effect: UIBlurEffect(style: style))
+    }
+
+    func updateUIView(_ uiView: UIVisualEffectView, context: Context) {
+        uiView.effect = UIBlurEffect(style: style)
+    }
+}

ElementX/Sources/Screens/CallScreen/View/CallScreen.swift

@@ -26,7 +26,6 @@ struct CallScreen: View {
                             Image(systemSymbol: .chevronBackward)
                                 .fontWeight(.semibold)
                         }
-                        // .padding(.leading, -8) // Fixes the button alignment, but harder to tap.
                     }
                 }
         }

ElementX/Sources/Screens/FilePreviewScreen/MediaFileManager.swift

@@ -0,0 +1,8 @@
+//
+// Copyright 2024 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+//
+
+import Foundation

ElementX/Sources/Screens/FilePreviewScreen/TimelineMediaPreviewCoordinator.swift

@@ -0,0 +1,69 @@
+//
+// Copyright 2024 New Vector Ltd.
+//
+// SPDX-License-Identifier: AGPL-3.0-only
+// Please see LICENSE in the repository root for full details.
+//
+
+import Combine
+import SwiftUI
+
+struct TimelineMediaPreviewContext {
+    /// The initial item to preview from the provided timeline.
+    /// This item's `id` will be used as the navigation transition's `sourceID`.
+    let item: EventBasedMessageTimelineItemProtocol
+    /// The timeline that the preview comes from, to allow for swiping to other media.
+    let viewModel: TimelineViewModelProtocol
+    /// The namespace that the navigation transition's `sourceID` should be defined in.
+    let namespace: Namespace.ID
+}
+
+struct TimelineMediaPreviewCoordinatorParameters {
+    let context: TimelineMediaPreviewContext
+    let mediaProvider: MediaProviderProtocol
+    let userIndicatorController: UserIndicatorControllerProtocol
+}
+
+enum TimelineMediaPreviewCoordinatorAction {
+    case viewInRoomTimeline(TimelineItemIdentifier)
+    case dismiss
+}
+
+final class TimelineMediaPreviewCoordinator: CoordinatorProtocol {
+    private let parameters: TimelineMediaPreviewCoordinatorParameters
+    private let viewModel: TimelineMediaPreviewViewModel
+
+    private var cancellables = Set<AnyCancellable>()
+
+    private let actionsSubject: PassthroughSubject<TimelineMediaPreviewCoordinatorAction, Never> = .init()
+    var actionsPublisher: AnyPublisher<TimelineMediaPreviewCoordinatorAction, Never> {
+        actionsSubject.eraseToAnyPublisher()
+    }
+
+    init(parameters: TimelineMediaPreviewCoordinatorParameters) {
+        self.parameters = parameters
+
+        viewModel = TimelineMediaPreviewViewModel(context: parameters.context,
+                                                  mediaProvider: parameters.mediaProvider,
+                                                  userIndicatorController: parameters.userIndicatorController)
+    }
+
+    func start() {
+        viewModel.actions.sink { [weak self] action in
+            MXLog.info("Coordinator: received view model action: \(action)")
+
+            guard let self else { return }
+            switch action {
+            case .viewInRoomTimeline(let itemID):
+                actionsSubject.send(.viewInRoomTimeline(itemID))
+            case .dismiss:
+                actionsSubject.send(.dismiss)
+            }
+        }
+        .store(in: &cancellables)
+    }
+
+    func toPresentable() -> AnyView {
+        AnyView(TimelineMediaPreviewView(context: viewModel.context))
+    }
+}