private void Button_confirm_edit(object sender, RoutedEventArgs e)
        {
            if (sessionViewModel.SelectedItem.Date.Length != 0 && sessionViewModel.SelectedItem.Timeslot_1.Length != 0 &&
                sessionViewModel.SelectedItem.Title.Length != 0 && sessionViewModel.SelectedItem.Speaker_1.Length != 0 &&
                sessionViewModel.SelectedItem.Room_1.Length != 0
                )
            {
                // check if there is already a session going on the new room being edited to
                // check newRoom == anotherRoom timeslot and date

                //datePicker1
                //timeslotComboBox
                //roomComboBox
                //speakerComboBox
                //titleTextBox



                Session a = sessionViewModel.SelectedItem;


                if (sessionViewModel.checkIfExists(sessionViewModel.SelectedItem))
                {
                    MessageBox.Show("This Room is taken on this timeslot and Date");
                    return;
                }

                sessionViewModel.EditSession(sessionViewModel.SelectedItem);
                MyDialogHost.IsOpen = false;
            }
            else
            {
                MessageBox.Show("Fields cannot be empty");
            }
        }