Third Party Photon PUN - How to handle OnRoomListUpdate function?

I'm trying to list of rooms in my game, however, I couldn't understand how OnRoomListUpdate works. This is my code to list the rooms:

Code (CSharp):

1.     List<RoomInfo> Rooms = new List<RoomInfo>();
2.  
3.     public override void OnRoomListUpdate(List<RoomInfo> roomList)
4.     {
5.         Rooms.Clear();
6.         foreach (var item in roomList)
7.         {
8.             if (!item.IsVisible || !item.IsOpen || item.RemovedFromList)
9.                 continue;
10.  
11.             Rooms.Add(item);
12.         }
13.  
14.         // ... clear the all rooms from the UI
15.         // ... fill the UI with the new 'Rooms' variable
16.     }

The function sometimes return a list with zero element even though there's an active room. What that function returns to me exactly and how can I list the room list.

 

You should not clear the list you got. The update is adding/removing rooms or updating their values. If you wipe the list and not much changes, you show far less rooms than available.

It may take a moment to update the room list on the Master Server (after a room got created) and the updates are sent in 5 or 10 second intervals (so the update to the client is not immediate either).

The update itself should not be empty entirely, unless you just joined the lobby (when you join, you get the initial list, which can be empty ofc).

 

So, that function only returns the rooms that are changed, but initially it returns the entire rooms in the lobby. Thank you.

 

Yes, exactly.
You could consider the first call an update, too, as the client knows of zero rooms.