Dictionary<string,RoomPanel> m_roomPanelList = new Dictionary<string,RoomPanel>();

 public override void OnRoomListUpdate(List<RoomInfo> roomList)
    {
        foreach (var entry in roomList)
        {
            if (m_roomPanelList.ContainsKey(entry.Name))
            {

                if (entry.RemovedFromList)
                {
                    RemoveRoomPanel(entry);
                }
            }
            else
            {
                if (!entry.RemovedFromList)
                {
                    AddRoomPanel(entry);
                }
            }
        }
    }

void AddRoomPanel(RoomInfo room)
    {
        var gbj = Instantiate(m_roomPanel, m_panelRect, false);
        var panel = gbj.GetComponent<RoomPanel>();

        panel.SetRoom(room);
        panel.JoinButton.onClick.AddListener(() => OnClickJoinRoom(panel.RoomName, room));
        m_roomPanelList.Add(room.Name,panel);
    }

    private void RemoveRoomPanel(RoomInfo room)
    {
        var panel = m_roomPanelList[room.Name];
        m_roomPanelList.Remove(room.Name);
        Destroy(panel.gameObject);
    }