public MainWindowViewModel()
        {
            MessageBoxCommand = new DelegateCommand(async() =>
            {
                var info = new MessageBoxNotification()
                {
                    Title   = "Confirm",
                    Content = "aaaaaaaaaaaaaaaaaaaaaaaaaa\nbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\ncccccc",
                    Icon    = MessageBoxNotification.IconType.Question,
                    Button  = MessageBoxNotification.ButtonType.OkCancel
                };

                var result = await MessageBoxRequest.RaiseAsync(info);
                Debug.WriteLine(result.Confirmed);
            });

            var notify = new SubWindowNotification();

            SubWindowShowCommand = new DelegateCommand(() =>
            {
                SubWindowRequest.Raise(notify);
            });

            SubWindowCloseCommand = new DelegateCommand(() =>
            {
                notify.DoClosing();
            });
        }