/// <summary>
/// Initializes a new instance of the <see cref="EditUniversityViewModel"/> class.
/// </summary>
/// <param name="dataService">
/// The data service.
/// </param>
/// <param name="navigationService">
/// The navigation service.
/// </param>
public EditUniversityViewModel(IDataService dataService, INavigationService navigationService)
{
_dataService = dataService;
_navigationService = navigationService;
_university = null;
SaveCommand =new RelayCommand(SaveUniversity);
CancelCommand =new RelayCommand(_navigationService.GoBack);
GoBackCommand = new RelayCommand(_navigationService.GoBack);
}
/// <summary>
/// Initializes a new instance of the <see cref="EditUniversityViewModel"/> class.
/// </summary>
/// <param name="dataService">
/// The data service.
/// </param>
/// <param name="navigationService">
/// The navigation service.
/// </param>
public EditUniversityViewModel(IDataService dataService, INavigationService navigationService)
{
_dataService = dataService;
_navigationService = navigationService;
_university = null;
LoadDataCommand = new RelayCommand(async () => await LoadDataAsync());
SaveCommand =new RelayCommand(SaveUniversity);
CancelCommand =new RelayCommand(_navigationService.GoBack);
}
/// <summary>
/// Deletes the university.
/// </summary>
/// <param name="selectedUniversity">The selected university.</param>
/// <returns>The <see cref="Task" />.</returns>
public async Task DeleteUniversityAsync(University selectedUniversity)
{
var students = await LoadStudentsByUniversityAsync(selectedUniversity);
await App.Connection.RunInTransactionAsync(async (SQLiteConnection connection) =>
{
foreach (var student in students)
{
DeleteStudentAsync(student);
}
App.Connection.DeleteAsync(selectedUniversity);
});
}
public void LoadData()
{
University = new University();
}
/// <summary>
/// Loads the data.
/// </summary>
/// <returns></returns>
public async Task LoadData(University university)
{
University = university;
Students = await _dataService.LoadStudentsByUniversityAsync(university);
}
/// <summary>
/// Loads the data.
/// </summary>
public void LoadData(University university)
{
Student = new Student { UniversityId = university.Id };
}
/// <summary>
/// Loads the data.
/// </summary>
/// <returns></returns>
public async Task LoadDataAsync()
{
try
{
var guid = _navigationService.QueryString["university"];
University = await this._dataService.LoadUniversityByIdAsync(guid);
}
catch (KeyNotFoundException)
{
University = new University();
}
}
/// <summary>
/// Loads the data.
/// </summary>
/// <returns></returns>
public void LoadData(University university)
{
University = university;
}
/// <summary>
/// Loads the students by university.
/// </summary>
/// <param name="university">The university.</param>
/// <returns></returns>
public async Task<IList<Student>> LoadStudentsByUniversityAsync(University university)
{
return await LoadStudentsByUniversityAsync(university.Id);
}
/// <summary>
/// Updates the university.
/// </summary>
/// <param name="selectedUniversity">The selected university.</param>
/// <returns>The <see cref="Task" />.</returns>
public async Task UpdateUniversityAsync(University selectedUniversity)
{
var existingContact = await App.Connection.FindAsync<University>(u => u.Id == selectedUniversity.Id);
if (existingContact != null)
{
await App.Connection.UpdateAsync(selectedUniversity);
}
}
/// <summary>
/// Saves the university.
/// </summary>
/// <param name="newUniversity">The new university.</param>
/// <returns>The <see cref="Task" />.</returns>
public async Task SaveUniversityAsync(University newUniversity)
{
await App.Connection.InsertAsync(newUniversity);
}