public MainWindow()
{
InitializeComponent();
_previewDialog = new ViewDialog();
_userCollection = new ObservableCollection <User>();
_userCollection.CollectionChanged += (e, v) => DisableButtons();
UsersListBox.ItemsSource = _userCollection;
DisableButtons();
}
private void ViewButton_OnClick(object sender, RoutedEventArgs e)
{
_previewDialog = new ViewDialog();
_previewDialog.User = _userPreview;
_previewDialog.Show();
}