public ReviewsViewModel(ICatalogueService catalogueService, INavigationService navigationService)
: base(catalogueService, navigationService)
{
Messenger.Default.Register <long>(this, async(cId) =>
{
SelectedCourseId = cId;
IsLoadingProgressRing = true;
ReviewsList = new ObservableCollection <CourReview>(await CatalogueService.GetCourseReviewByCourseId(cId));
IsLoadingProgressRing = false;
IsNoReviewMessageVisible = (ReviewsList.Count > 0) ? Visibility.Collapsed : Visibility.Visible;
});
}