public async Task <Message[]> GetAsync(string groupId, int currentPage)
        {
            var request  = $"{API_URL}?groupId={groupId}";
            var messages = await AuthorizedHttpClient.GetFromJsonAsync <Message[]>(request);

            messages.ToList().ForEach(async m => m.Username = await _userService.GetUserNameAsync(m.CreatedBy));
            return(messages);
        }
        private async Task OnReceiveMessageAsync(Message message)
        {
            message.Username = await _userService.GetUserNameAsync(message.CreatedBy);

            if (MessagesModels.ContainsKey(message.GroupId))
            {
                MessagesModels[message.GroupId].Add(message, false);
            }
            OnNewMessage(message.GroupId);
        }