Permalink Tweaks 2 (#2766)

* Missing changelog.

* Parse bare room aliases as permalinks.

Update the SDK.

* Fix tapping the same permalink twice.

Add a test.

Don't clear the focussed item when reaching the bottom of the timeline.

* Make sure sending a message returns to live.

ElementX/Sources/Screens/RoomScreen/RoomScreenModels.swift

@@ -85,6 +85,7 @@ enum RoomScreenViewAction {
     case sendReadReceiptIfNeeded(TimelineItemIdentifier)
     case paginateBackwards
     case paginateForwards
+    case scrollToBottom
     
     case timelineItemMenu(itemID: TimelineItemIdentifier)
     case timelineItemMenuAction(itemID: TimelineItemIdentifier, action: TimelineItemMenuAction)
@@ -112,11 +113,8 @@ enum RoomScreenViewAction {
     case focusOnEventID(String)
     /// Switch back to a live timeline (from a detached one).
     case focusLive
-    /// Remove the highlighted event without switching timeline.
-    ///
-    /// This is useful when returning to the bottom of the live timeline
-    ///  if `focusOnEventID` didn't use a detached timeline.
-    case clearFocussedEvent
+    /// The timeline scrolled to reveal the focussed item.
+    case scrolledToFocussedItem
 }
 
 enum RoomScreenComposerAction {
@@ -229,7 +227,10 @@ struct TimelineViewState {
     var isLive = true
     var paginationState = PaginationState.default
     
-    var focussedEventID: String?
+    /// The ID of the focussed event navigated to via a permalink.
+    var focussedEventID: String? { didSet { focussedEventNeedsDisplay = focussedEventID != nil } }
+    /// Whether the timeline should scroll to `focussedEventID` once its item has been built and added to the timeline.
+    var focussedEventNeedsDisplay: Bool
     
     // These can be removed when we have full swiftUI and moved as @State values in the view
     var scrollToBottomPublisher = PassthroughSubject<Void, Never>()

ElementX/Sources/Screens/RoomScreen/RoomScreenViewModel.swift

@@ -88,7 +88,8 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
                                                          roomAvatarURL: roomProxy.avatarURL,
                                                          timelineStyle: appSettings.timelineStyle,
                                                          isEncryptedOneToOneRoom: roomProxy.isEncryptedOneToOneRoom,
-                                                         timelineViewState: TimelineViewState(focussedEventID: focussedEventID),
+                                                         timelineViewState: TimelineViewState(focussedEventID: focussedEventID,
+                                                                                              focussedEventNeedsDisplay: focussedEventID != nil),
                                                          ownUserID: roomProxy.ownUserID,
                                                          hasOngoingCall: roomProxy.hasOngoingCall,
                                                          bindings: .init(reactionsCollapsed: [:])),
@@ -175,6 +176,8 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
             paginateBackwards()
         case .paginateForwards:
             paginateForwards()
+        case .scrollToBottom:
+            scrollToBottom()
         case .poll(let pollAction):
             processPollAction(pollAction)
         case .audio(let audioAction):
@@ -187,8 +190,9 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
             Task { await focusOnEvent(eventID: eventID) }
         case .focusLive:
             focusLive()
-        case .clearFocussedEvent:
-            state.timelineViewState.focussedEventID = nil
+        case .scrolledToFocussedItem:
+            // Use a Task to mutate view state after the current view update.
+            Task { state.timelineViewState.focussedEventNeedsDisplay = false }
         }
     }
 
@@ -365,7 +369,7 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
             .filter { $0 == .sentMessage }
             .receive(on: DispatchQueue.main)
             .sink { [weak self] _ in
-                self?.state.timelineViewState.scrollToBottomPublisher.send(())
+                self?.scrollToBottom()
             }
             .store(in: &cancellables)
 
@@ -488,6 +492,14 @@ class RoomScreenViewModel: RoomScreenViewModelType, RoomScreenViewModelProtocol
         }
     }
     
+    private func scrollToBottom() {
+        if state.timelineViewState.isLive {
+            state.timelineViewState.scrollToBottomPublisher.send(())
+        } else {
+            focusLive()
+        }
+    }
+    
     private func sendReadReceiptIfNeeded(for lastVisibleItemID: TimelineItemIdentifier) async {
         guard appMediator.appState == .active else { return }
                 

ElementX/Sources/Screens/RoomScreen/View/RoomScreen.swift

@@ -103,7 +103,7 @@ struct RoomScreen: View {
     }
     
     private var scrollToBottomButton: some View {
-        Button(action: scrollToBottom) {
+        Button { context.send(viewAction: .scrollToBottom) } label: {
             Image(systemName: "chevron.down")
                 .font(.compound.bodyLG)
                 .fontWeight(.semibold)
@@ -121,20 +121,13 @@ struct RoomScreen: View {
         .opacity(isAtBottomAndLive ? 0.0 : 1.0)
         .accessibilityHidden(isAtBottomAndLive)
         .animation(.elementDefault, value: isAtBottomAndLive)
+        .accessibilityIdentifier(A11yIdentifiers.roomScreen.scrollToBottom)
     }
     
     private var isAtBottomAndLive: Bool {
         context.isScrolledToBottom && context.viewState.timelineViewState.isLive
     }
     
-    private func scrollToBottom() {
-        if context.viewState.timelineViewState.isLive {
-            context.viewState.timelineViewState.scrollToBottomPublisher.send(())
-        } else {
-            context.send(viewAction: .focusLive)
-        }
-    }
-    
     @ViewBuilder
     private var loadingIndicator: some View {
         if context.viewState.showLoading {

ElementX/Sources/Screens/RoomScreen/View/Timeline/TimelineTableViewController.swift

@@ -76,10 +76,10 @@ class TimelineTableViewController: UIViewController {
     }
     
     /// There are pending items in `timelineItemsDictionary` that haven't been applied to the data source.
-    var hasPendingItems = false
+    private var hasPendingItems = false
     
     /// The user is dragging the scroll view (or it is still decelerating after a drag).
-    var isDraggingScrollView = false {
+    private var isDraggingScrollView = false {
         didSet {
             if !isDraggingScrollView, hasPendingItems {
                 hasPendingItems = false
@@ -104,19 +104,17 @@ class TimelineTableViewController: UIViewController {
         }
     }
     
-    /// The ID of the focussed event if opening the room to an event permalink.
-    var focussedEventID: String? {
-        didSet {
-            guard let focussedEventID else { return }
-            
-            focussedEventNeedsDisplay = true
-            scrollToItem(eventID: focussedEventID, animated: false)
-        }
-    }
+    /// The ID of the focussed event if navigating to an event permalink within the room.
+    var focussedEventID: String?
 
     /// Whether the timeline should scroll to `focussedEventID` when that item is added to the data source.
     /// This is necessary as the focussed event can be set before the timeline builder has built its item.
-    var focussedEventNeedsDisplay = false
+    var focussedEventNeedsDisplay = false {
+        didSet {
+            guard focussedEventNeedsDisplay, let focussedEventID else { return }
+            scrollToItem(eventID: focussedEventID, animated: false)
+        }
+    }
     
     /// Used to hold an observable object that the typing indicator can use
     let typingMembers = TypingMembersObservableObject(members: [])
@@ -173,10 +171,7 @@ class TimelineTableViewController: UIViewController {
         
         scrollToBottomPublisher
             .sink { [weak self] _ in
-                guard let self else { return }
-                
-                scrollToNewestItem(animated: true)
-                coordinator.send(viewAction: .clearFocussedEvent)
+                self?.scrollToNewestItem(animated: true)
             }
             .store(in: &cancellables)
         
@@ -343,7 +338,7 @@ class TimelineTableViewController: UIViewController {
         if let kvPair = timelineItemsDictionary.first(where: { $0.value.identifier.eventID == focussedEventID }),
            let indexPath = dataSource?.indexPath(for: kvPair.key) {
             tableView.scrollToRow(at: indexPath, at: .middle, animated: animated)
-            focussedEventNeedsDisplay = false
+            coordinator.send(viewAction: .scrolledToFocussedItem)
         }
     }
     

ElementX/Sources/Screens/RoomScreen/View/Timeline/TimelineView.swift

@@ -65,6 +65,9 @@ struct TimelineView: UIViewControllerRepresentable {
             if tableViewController.focussedEventID != context.viewState.timelineViewState.focussedEventID {
                 tableViewController.focussedEventID = context.viewState.timelineViewState.focussedEventID
             }
+            if tableViewController.focussedEventNeedsDisplay != context.viewState.timelineViewState.focussedEventNeedsDisplay {
+                tableViewController.focussedEventNeedsDisplay = context.viewState.timelineViewState.focussedEventNeedsDisplay
+            }
             
             if tableViewController.typingMembers.members != context.viewState.typingMembers {
                 tableViewController.setTypingMembers(context.viewState.typingMembers)