private void btn_Save_Click(object sender, RoutedEventArgs e)
        {
            ChosenPlayer.FirstName = txt_FirstName.Text;
            ChosenPlayer.LastName  = txt_LastName.Text;
            ChosenPlayer.Email     = txt_Email.Text;
            ChosenPlayer.PhoneNr   = txt_PhoneNr.Text;

            BusinessFacade.UpdatePlayer(ChosenPlayer);
        }