private void ShowItemData(string date, long id)
        {
            AssignmentsFormWindow assignmentWindow = new AssignmentsFormWindow(date, id);

            assignmentWindow.ShowDialog();

            if (assignmentWindow.DialogResult.HasValue && assignmentWindow.DialogResult.Value)
            {
                Refresh();
            }
        }
        private void AddAssignment_Click(object sender, RoutedEventArgs e)
        {
            AssignmentsFormWindow assignmentWindow = new AssignmentsFormWindow(TxtDateFrame.Text.ToString(), 0);

            assignmentWindow.ShowDialog();

            if (assignmentWindow.DialogResult.HasValue && assignmentWindow.DialogResult.Value)
            {
                Refresh();
            }
        }
        private void ShowAssignmentButton_Click(object sender, RoutedEventArgs e)
        {
            if (_viewModel.SelectedAssignment != null)
            {
                AssignmentsFormWindow assignmentWindow = new AssignmentsFormWindow(TxtDateFrame.Text.ToString(), _viewModel.SelectedAssignment.Id);
                assignmentWindow.ShowDialog();

                if (assignmentWindow.DialogResult.HasValue && assignmentWindow.DialogResult.Value)
                {
                    Refresh();
                }
            }
            else
            {
                MessageBoxResult result = MessageBox.Show("Para ver el detalle de una asignaciĆ³n, primero selecciona un elemento de la lista",
                                                          "Confirmation",
                                                          MessageBoxButton.OK,
                                                          MessageBoxImage.Warning);
            }
        }