private void SendNewUserMessage()
        {
            var newUserMessageWindow = new NewUserMessageWindow();
            var messageViewModel     = new MessageViewModel(CurrentUser, selectedEmployee, this, newUserMessageWindow);

            newUserMessageWindow.DataContext = messageViewModel;

            newUserMessageWindow.Show();
        }
        public MessageViewModel(Employee currentUser, Employee selectedUser, MainViewModel mainViewModel, NewUserMessageWindow newUserMessageWindow)
        {
            CurrentUser  = currentUser;
            SelectedUser = selectedUser;

            CurrentMessage = new Message();

            this.mainViewModel        = mainViewModel;
            this.newUserMessageWindow = newUserMessageWindow;
        }