private async void OnSelectedDirectConversation()
        {
            if (SelectedChannel != null)
            {
                SelectedChannel.HasUnreadedMessages = false;
                SelectedChannel.ChannelFontWeight   = FontWeights.Normal;
                var messages = await rocketChatRest.GetDirectMessages(SelectedChannel.Id);

                foreach (var message in messages)
                {
                    message.User = Users.FirstOrDefault(x => x.Id == message.User.Id);
                    if (message.Attachments != null && message.Attachments.Length > 0)
                    {
                        foreach (var attachment in message.Attachments)
                        {
                            attachment.ImagePreview = await rocketChatRest.GetImage(attachment.ImageUrl);
                        }
                    }
                }
                Messages = new ObservableCollection <Message>(messages);
            }
        }