public async void OnSelected()
 {
     if (SelectedItem != null)
     {
         Args.CourseId = SelectedItem.CourseId;
         await CourseDetailsViewModel.LoadAsync(Args);
     }
 }
 protected override async void OnNew()
 {
     Args.CourseId = -1;
     await CourseDetailsViewModel.LoadAsync(Args);
 }
 public StudentCourseRecordListViewModel(IDialogService dialogService, IStudentScoreService studentScoreService) : base(dialogService)
 {
     StudentScoreService    = studentScoreService;
     CourseDetailsViewModel = new CourseDetailsViewModel(dialogService, studentScoreService);
     Args = new CourseArgs();
 }