Concurrency Fixes (#283)

* Review places where MainActor used * Adapt to MainActor changes, avoid redundant task detachments * Move Rust client operations into a dedicated concurrent queue, make init async * Add changelog * Fixed small working for awaiting non-async method * Remove some redundant tasks * Put back some main actors * Fix tests * Fixed timeline updates when the number of items doesn't change. Keeps more previous home screen room data between reloads Co-authored-by: Stefan Ceriu <stefanc@matrix.org>
2026-11-02 21:33:26 +00:00 · 2022-11-02 18:25:46 +03:00
parent 965569aae2
commit f6a599a51b
19 changed files with 243 additions and 221 deletions
@@ -23,6 +23,7 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
    private let userSession: UserSessionProtocol
    private let roomSummaryProvider: RoomSummaryProviderProtocol
    private let attributedStringBuilder: AttributedStringBuilderProtocol
+    private var roomsForIdentifiers = [String: HomeScreenRoom]()
    
    var callback: ((HomeScreenViewModelAction) -> Void)?
    
@@ -72,9 +73,7 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
        roomSummaryProvider.roomListPublisher
            .receive(on: DispatchQueue.main)
            .sink { [weak self] _ in
-                Task {
-                    await self?.updateRooms()
-                }
+                self?.updateRooms()
            }
            .store(in: &cancellables)
        
@@ -91,10 +90,8 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
                state.userDisplayName = userDisplayName
            }
        }
-        
-        Task {
-            await updateRooms()
-        }
+
+        updateRooms()
    }
    
    // MARK: - Public
@@ -117,52 +114,58 @@ class HomeScreenViewModel: HomeScreenViewModelType, HomeScreenViewModelProtocol
    // MARK: - Private
    
    private func loadDataForRoomIdentifier(_ identifier: String) {
-        guard let summary = roomSummaryProvider.roomListPublisher.value.first(where: { $0.asFilled?.id == identifier })?.asFilled,
-              let homeRoomIndex = state.rooms.firstIndex(where: { $0.id == identifier }) else {
+        guard let roomSummary = roomSummaryProvider.roomListPublisher.value.first(where: { $0.asFilled?.id == identifier })?.asFilled,
+              let roomIndex = state.rooms.firstIndex(where: { $0.id == identifier }) else {
            return
        }
        
-        var details = state.rooms[homeRoomIndex]
+        var room = state.rooms[roomIndex]
            
-        guard details.avatar == nil,
-              let avatarURLString = summary.avatarURLString else {
+        guard room.avatar == nil,
+              let avatarURLString = roomSummary.avatarURLString else {
            return
        }
        
        Task {
            if case let .success(image) = await userSession.mediaProvider.loadImageFromURLString(avatarURLString, avatarSize: .room(on: .home)) {
-                details.avatar = image
-                state.rooms[homeRoomIndex] = details
+                room.avatar = image
+                state.rooms[roomIndex] = room
+                roomsForIdentifiers[roomSummary.id] = room
            }
        }
    }
    
-    private func updateRooms() async {
-        state.rooms = await Task.detached {
-            var rooms = [HomeScreenRoom]()
-            
-            for summary in self.roomSummaryProvider.roomListPublisher.value {
-                switch summary {
-                case .empty(let id):
-                    rooms.append(HomeScreenRoom.placeholder(id: id))
-                case .filled(let summary):
-                    let avatarImage = await self.userSession.mediaProvider.imageFromURLString(summary.avatarURLString, avatarSize: .room(on: .home))
-                    
-                    var timestamp: String?
-                    if let lastMessageTimestamp = summary.lastMessageTimestamp {
-                        timestamp = lastMessageTimestamp.formatted(date: .omitted, time: .shortened)
-                    }
-                    
-                    rooms.append(HomeScreenRoom(id: summary.id,
-                                                name: summary.name,
-                                                hasUnreads: summary.unreadNotificationCount > 0,
-                                                timestamp: timestamp,
-                                                lastMessage: summary.lastMessage,
-                                                avatar: avatarImage))
+    private func updateRooms() {
+        var rooms = [HomeScreenRoom]()
+        var newRoomsForIdentifiers = [String: HomeScreenRoom]()
+        
+        for summary in roomSummaryProvider.roomListPublisher.value {
+            switch summary {
+            case .empty(let id):
+                rooms.append(HomeScreenRoom.placeholder(id: id))
+            case .filled(let summary):
+                let oldRoom = roomsForIdentifiers[summary.id]
+                
+                let avatarImage = userSession.mediaProvider.imageFromURLString(summary.avatarURLString, avatarSize: .room(on: .home))
+                
+                var timestamp: String?
+                if let lastMessageTimestamp = summary.lastMessageTimestamp {
+                    timestamp = lastMessageTimestamp.formatted(date: .omitted, time: .shortened)
                }
+                
+                let room = HomeScreenRoom(id: summary.id,
+                                          name: summary.name,
+                                          hasUnreads: summary.unreadNotificationCount > 0,
+                                          timestamp: timestamp ?? oldRoom?.timestamp,
+                                          lastMessage: summary.lastMessage ?? oldRoom?.lastMessage,
+                                          avatar: avatarImage ?? oldRoom?.avatar)
+                
+                rooms.append(room)
+                newRoomsForIdentifiers[summary.id] = room
            }
-            
-            return rooms
-        }.value
+        }
+        
+        state.rooms = rooms
+        roomsForIdentifiers = newRoomsForIdentifiers
    }
 }