/** Method initializes a process of saving and absance model to the database */
        private void saveButton_Click(object sender, EventArgs e)
        {
            if (!this.isDateTimeValid())
            {
                feedbackWindow.setCustomizedMessage(validationMessage);
                feedbackWindow.ShowDialog();
                validationMessage = "";
                return;
            }
            AbsenceModel absence = this.getAbsenceModelFromPresenterForm();

            List <string>     invalidFields = new List <string>();
            AbsenceController controller    = new AbsenceController();

            if (allTheDoctors.Enabled)
            {
                invalidFields = controller.isDataValid(startDatePicker, endDatePicker, startTimePicker, endTimePicker, invalidFields, allTheDoctors);
            }
            else
            {
                invalidFields = controller.isDataValid(startDatePicker, endDatePicker, startTimePicker, endTimePicker, invalidFields);
            }
            if (invalidFields == null || invalidFields.Count == 0)
            {
                if (!controller.save(absence))
                {
                    this.feedbackWindow.setMessageForAbsencesProblems();
                }
                else
                {
                    this.feedbackWindow.setMessageForSuccessfullOperation();
                }
            }
            else
            {
                feedbackWindow.setMessageForInvalidFieldsValues(invalidFields);
            }
            feedbackWindow.ShowDialog();
        }
        private void FinishedExerciseClick(object param)
        {
            FeedbackWindow    window = new FeedbackWindow();
            FeedbackViewModel vm     = new FeedbackViewModel(window);

            window.DataContext = vm;

            Feedback feedback = Feedback.Medium;
            bool?    result   = window.ShowDialog();

            if (result == true)
            {
                feedback = vm.UserFeedback;
            }
            try
            {
                CurrentUser.ExerciseCompleted(feedback);
            }
            catch (SqlException)
            {
                MessageBox.Show($"Kunne ikke oprette forbindelse til databasen!");
            }
            UpdateExerciseDesc();
        }