/// <summary>
 /// Constructor to edit data of an existing article.
 /// </summary>
 /// <param name="parentViewModel"></param>
 /// <param name="article"></param>
 public ArticleEditViewModel(ArticleView.ArticleTabViewModel parentViewModel, Article article)
 {
     ParentViewModel = parentViewModel;
     EditContentTabs = new ObservableCollection<UIElement>();
     ContextualTabGroup = parentViewModel.ContextualTabGroup;
     EditContentTabs.Add(new Contextual.Controls.ArticleEditControlTabItem());
     Article = article;
     EditMode = true;
     TabItem = new ArticleEditTabItem(this);
     Content = new ArticleEditTabContent(this);
 }
 /// <summary>
 /// Constructor if you want to create a new article.
 /// </summary>
 /// <param name="parentViewModel"></param>
 public ArticleEditViewModel(ArticleView.ArticleTabViewModel parentViewModel, int ID = -1)
 {
     ParentViewModel = parentViewModel;
     EditContentTabs = new ObservableCollection<UIElement>();
     ContextualTabGroup = parentViewModel.ContextualTabGroup;
     EditContentTabs.Add(new Contextual.Controls.ArticleEditControlTabItem());
     Article = new Article();
     if (ID != -1)
         Article.ArticleID = ID.ToString();
     EditMode = false;
     TabItem = new ArticleEditTabItem(this);
     Content = new ArticleEditTabContent(this);
 }