private void filiereComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e) { string selectedFil = filiereComboBox.Items[filiereComboBox.SelectedIndex].ToString(); studentsListView.ItemsSource = collectionStudents.Where(etd => etd.Filiere.Nom_filiere == selectedFil); nomFil.Content = selectedFil; responsableFil.Content = ManagerDB.getResponsable(selectedFil); }