public BookmarkSearchPageViewModel(
     INavigationService navigationService,
     IBookmarkRepository bookmarkRepository,
     BookmarksController bookmarksController,
     IBookRepository bookRepository,
     IBusyIndicatorManager busyIndicatorManager)
 {
     _navigationService = navigationService;
     _bookmarkRepository = bookmarkRepository;
     _bookmarksController = bookmarksController;
     _bookRepository = bookRepository;
     _busyIndicatorManager = busyIndicatorManager;
 }
 public ThisBookBookmarksViewModel(
     INavigationService navigationService,
     BookmarksController bookmarksController, 
     IBookmarkRepository bookmarkService,
     IBookRepository bookService,
     IBusyIndicatorManager busyIndicatorManager,
     IEventAggregator eventAggregator) : base(navigationService, bookmarkService, eventAggregator)
 {
     _bookmarksController = bookmarksController;
     _bookmarkService = bookmarkService;
     _bookRepository = bookService;
     _busyIndicatorManager = busyIndicatorManager;
     DisplayName = UIStrings.BookmarksPivot_ThisBook;
 }