async Task GetCourses()
{
try
{
this.IsRefreshing = true;
var connection = await courseService.CheckConnection();
if (!connection)
{
this.IsRefreshing = false;
await Application.Current.MainPage.DisplayAlert("Error", "No internet connection", "Cancel");
return;
}
var listCourses = (await courseService.GetAll(Endpoints.GET_COURSES)).Select(x => ToCourseItemViewModel(x));
this.AllCourses = listCourses.ToList();
this.Courses = new ObservableCollection <CourseItemViewModel>(listCourses);
this.IsRefreshing = false;
}
catch (Exception ex)
{
this.IsRefreshing = false;
await Application.Current.MainPage.DisplayAlert("Error", ex.Message, "Cancel");
}
}
async Task DeleteCourse()
{
var answer = await Application.Current.MainPage.DisplayAlert("Confirm", "Delete confirm", "Yes", "No");
if (!answer)
{
return;
}
var connection = await courseService.CheckConnection();
if (!connection)
{
await Application.Current.MainPage.DisplayAlert("Error", "No internet connection", "Cancel");
return;
}
await courseService.Delete(Endpoints.DELETE_COURSES, this.CourseID);
await Application.Current.MainPage.DisplayAlert("Message", "The process is successful", "Confirm");
var courseViewModel = CoursesViewModel.GetInstance();
var courseDeleted = courseViewModel.AllCourses.FirstOrDefault(x => x.CourseID == this.CourseID);
courseViewModel.AllCourses.Remove(courseDeleted);
courseViewModel.GetCoursesByTitle();
}
async Task CreateCourse()
{
try
{
if (string.IsNullOrEmpty(this.Title))
{
await Application.Current.MainPage.DisplayAlert("Error", "You must enter the field title", "Cancel");
return;
}
this.IsRunning = true;
this.IsEnabled = false;
var connection = await courseService.CheckConnection();
if (!connection)
{
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Error", "No internet connection", "Cancel");
return;
}
var courseDTO = new CourseDTO {
CourseID = this.CourseID, Title = this.Title, Credits = this.Credits
};
await courseService.Create(Endpoints.POST_COURSES, courseDTO);
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Message", "The process is successful", "Cancel");
this.CourseID = this.Credits = 0;
this.Title = string.Empty;
Application.Current.MainPage = new NavigationPage(new CoursesPage());
//var enrollmentDate = DateTime.UtcNow;
//this.EnrollmentDate = DateTime.UtcNow;
}
catch (Exception ex)
{
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Error", ex.Message, "Cancel");
}
}
async Task EditCourse()
{
try
{
if (string.IsNullOrEmpty(this.Course.Title))
{
await Application.Current.MainPage.DisplayAlert("Error", "You must enter the title field", "Cancel");
return;
}
this.IsRunning = true;
this.IsEnabled = false;
var connection = await courseService.CheckConnection();
if (!connection)
{
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Error", "No internet connection", "Cancel");
return;
}
var courseDTO = new CourseDTO {
CourseID = this.Course.CourseID, Title = this.Course.Title, Credits = this.Course.Credits
};
await courseService.Update(Endpoints.PUT_COURSES, this.Course.CourseID, courseDTO);
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Message", "The process is successful", "Confirm");
this.Course.CourseID = this.Course.Credits = 0;
this.Course.Title = string.Empty;
await Application.Current.MainPage.Navigation.PopAsync();
}
catch (Exception ex)
{
this.IsRunning = false;
this.IsEnabled = true;
await Application.Current.MainPage.DisplayAlert("Error", ex.Message, "Cancel");
}
}