/// <summary>
        /// Handles clicking of the 'Yes' button. Delete the target entity and related entities etc. and close the window.
        /// </summary>
        /// <param name="sender">The 'Yes' button.</param>
        /// <param name="arguments">Parameters for the event.</param>
        private void OnOkay(object sender, RoutedEventArgs arguments)
        {
            WindowDeleteProgress deleteEntity = new WindowDeleteProgress();

            deleteEntity.DeleteList = this.DeleteList;
            this.Close();
            deleteEntity.Show();
        }
        /// <summary>
        /// Handles clicking of the 'Yes' button. Delete the target entity and related entities etc. and close the window.
        /// </summary>
        /// <param name="sender">The 'Yes' button.</param>
        /// <param name="arguments">Parameters for the event.</param>
        private void OnOkay(object sender, RoutedEventArgs arguments)
        {
            WindowDeleteProgress deleteEntity = new WindowDeleteProgress();

            deleteEntity.DeleteList = new List <GuardianObject>();
            deleteEntity.DeleteList.Add(this.Entity);
            this.Close();
            deleteEntity.Show();
        }