private async void BodyControl_ItemClicked(object sender, BookShelfControl.ItemClickedEventArgs e)
 {
     if (e.SelectedItem is BookShelfViewModels.BookViewModel)
     {
         var book = await (e.SelectedItem as BookShelfViewModels.BookViewModel).TryGetBook();
         if (book != null && book is Books.IBookFixed)
         {
             var param = new BookFixed2Viewer.BookAndParentNavigationParamater() { BookViewerModel = book as Books.IBookFixed, BookShelfModel = e.SelectedItem as BookShelfViewModels.BookViewModel,Title= (e.SelectedItem as BookShelfViewModels.BookViewModel).Title };
             this.Frame.Navigate(typeof(BookFixed2Viewer), param);
         }
     }
 }
 private async void BodyControl_ItemClicked(object sender, BookShelfControl.ItemClickedEventArgs e)
 {
     if (e.SelectedItem is BookShelfViewModels.BookViewModel)
     {
         var book = await(e.SelectedItem as BookShelfViewModels.BookViewModel).TryGetBook();
         if (book != null && book is Books.IBookFixed)
         {
             var param = new BookFixed2Viewer.BookAndParentNavigationParamater()
             {
                 BookViewerModel = book as Books.IBookFixed, BookShelfModel = e.SelectedItem as BookShelfViewModels.BookViewModel, Title = (e.SelectedItem as BookShelfViewModels.BookViewModel).Title
             };
             this.Frame.Navigate(typeof(BookFixed2Viewer), param);
         }
     }
 }