workaround for fixing the loading screen never going away on clients if the main menu scene switches too fast.

Author: SamuelBellomo

Assets/BossRoom/Scripts/Shared/Net/ConnectionManagement/ClientGameNetPortal.cs

@@ -142,17 +142,14 @@ public void OnConnectFinished(ConnectStatus status)
             }
         }
 
-        private void OnDisconnectReasonReceived(ConnectStatus status)
-        {
-            DisconnectReason.SetDisconnectReason(status);
-        }
-
-        private void OnDisconnectOrTimeout(ulong clientID)
+        void OnDisconnectOrTimeout(ulong clientID)
         {
             // This is also called on the Host when a different client disconnects. To make sure we only handle our own disconnection, verify that we are either
             // not a host (in which case we know this is about us) or that the clientID is the same as ours if we are the host.
             if (!NetworkManager.Singleton.IsHost || NetworkManager.Singleton.IsHost && NetworkManager.Singleton.LocalClientId == clientID)
             {
+                SceneLoaderWrapper.Instance.IsClosingClients = false; // disconnect done
+
                 //On a client disconnect we want to take them back to the main menu.
                 //We have to check here in SceneManager if our active scene is the main menu, as if it is, it means we timed out rather than a raw disconnect;
                 if (SceneManager.GetActiveScene().name != "MainMenu")
@@ -307,7 +304,8 @@ public static void ReceiveServerToClientConnectResult_CustomMessage(ulong client
         public static void ReceiveServerToClientSetDisconnectReason_CustomMessage(ulong clientID, FastBufferReader reader)
         {
             reader.ReadValueSafe(out ConnectStatus status);
-            Instance.OnDisconnectReasonReceived(status);
+            Instance.DisconnectReason.SetDisconnectReason(status);
+            SceneLoaderWrapper.Instance.IsClosingClients = true;
         }
     }
 }

Assets/BossRoom/Scripts/Shared/Net/ConnectionManagement/ServerGameNetPortal.cs

@@ -110,15 +110,20 @@ public void OnUserDisconnectRequest()
             {
                 SendServerToAllClientsSetDisconnectReason(ConnectStatus.HostDisconnected);
                 // wait before shutting down to make sure those messages get sent before the clients disconnect.
-                StartCoroutine(WaitToShutdown());
+                StartCoroutine(WaitToShutdown()); // todo in theory, according to "Shutdown"'s doc, we shouldn't need this wait anymore.
             }
         }
 
         IEnumerator WaitToShutdown()
         {
-            yield return new WaitForSeconds(0.5f);
+            // todo netmanager should really be shutting down instead of us having to manually flag that we're shutting down
+            SceneLoaderWrapper.Instance.IsClosingClients = true;
+            yield return null; // todo still needed? wait for UTP's update for it to send it's batched messages
+            yield return null;
             SessionManager<SessionPlayerData>.Instance.OnUserDisconnectRequest();
+            Debug.Log("shutdown");
             m_Portal.NetManager.Shutdown();
+            SceneLoaderWrapper.Instance.IsClosingClients = false;
         }
 
         private void Clear()
@@ -243,6 +248,7 @@ public void SendServerToClientSetDisconnectReason(ulong clientID, ConnectStatus
             writer.WriteValueSafe(status);
             NetworkManager.Singleton.CustomMessagingManager.SendNamedMessage(nameof(ClientGameNetPortal.ReceiveServerToClientSetDisconnectReason_CustomMessage), clientID, writer);
         }
+
         /// <summary>
         /// Sends a DisconnectReason to all connected clients. This should only be done on the server, prior to disconnecting the clients.
         /// </summary>

Packages/com.unity.multiplayer.samples.coop/Utilities/SceneManagement/SceneLoaderWrapper.cs

@@ -88,16 +88,24 @@ public void LoadScene(string sceneName, LoadSceneMode loadSceneMode = LoadSceneM
             }
         }
 
+        public bool IsClosingClients { get; set; }
+
         void OnSceneLoaded(Scene scene, LoadSceneMode loadSceneMode)
         {
-            if (m_NetworkManager == null || !m_NetworkManager.IsListening || m_NetworkManager.ShutdownInProgress || !m_NetworkManager.NetworkConfig.EnableSceneManagement)
+            // we're letting networked scene loading handle our loading screen, since there's still some loading happening after unity scene loading is done.
+            // in case we're offline, then we let unity's scene loader tell us when to turn off the loading screen.
+            var isOffline = m_NetworkManager == null || !m_NetworkManager.IsListening || m_NetworkManager.ShutdownInProgress || !m_NetworkManager.NetworkConfig.EnableSceneManagement;
+            // TODO this can be called while we're still in the WaitForSeconds(0.5) while shutting down host side. which means we'll still be in theory connected. Waiting on fix
+            // for this in MTT-2821
+            if (isOffline || IsClosingClients)
             {
                 m_ClientLoadingScreen.StopLoadingScreen();
             }
         }
 
         void OnSceneEvent(SceneEvent sceneEvent)
         {
+            Debug.Log($"on scene event: {sceneEvent.SceneEventType}");
             // Only executes on client
             if (m_NetworkManager.IsClient)
             {