public TeacherSelectViewData GetTeacherSelectionViewData()
        {
            TeacherSelectViewData viewData = new TeacherSelectViewData();
            viewData.Persons = new System.Collections.ObjectModel.ObservableCollection<PersonListItemViewData>();

            foreach (var teacher in TeacherContext.GetTeachers())
            {
                viewData.Persons.Add(new TeacherListItemViewData()
                {
                    Id = teacher.Id,
                    Name = teacher.Name
                });
            }
            return viewData;
        }
 /// <summary>
 /// The Constructer for TeacherSelectViewModel
 /// </summary>
 public TeacherSelectViewModel()
 {
     Person = new TeacherSelectViewData();
     addTeachersToPersons();
 }