///--------------------------------------------------------------------------------
        /// <summary>This method updates the view model data and sends update command back
        /// to the solution builder.</summary>
        ///--------------------------------------------------------------------------------
        protected override void OnUpdate()
        {
            // set up reverse engineering instance if not present
            if (IndexProperty.ReverseInstance == null && IndexProperty.IsAutoUpdated == true)
            {
                IndexProperty.ReverseInstance = new IndexProperty();
                IndexProperty.ReverseInstance.TransformDataFromObject(IndexProperty, null, false);

                // perform the update of EditIndexProperty back to IndexProperty
                IndexProperty.TransformDataFromObject(EditIndexProperty, null, false);
                IndexProperty.IsAutoUpdated = false;
            }
            else if (IndexProperty.ReverseInstance != null)
            {
                EditIndexProperty.ResetModified(IndexProperty.ReverseInstance.IsModified);
                if (EditIndexProperty.Equals(IndexProperty.ReverseInstance))
                {
                    // perform the update of EditIndexProperty back to IndexProperty
                    IndexProperty.TransformDataFromObject(EditIndexProperty, null, false);
                    IndexProperty.IsAutoUpdated = true;
                }
                else
                {
                    // perform the update of EditIndexProperty back to IndexProperty
                    IndexProperty.TransformDataFromObject(EditIndexProperty, null, false);
                    IndexProperty.IsAutoUpdated = false;
                }
            }
            else
            {
                // perform the update of EditIndexProperty back to IndexProperty
                IndexProperty.TransformDataFromObject(EditIndexProperty, null, false);
                IndexProperty.IsAutoUpdated = false;
            }
            IndexProperty.ForwardInstance = null;
            if (PropertyIDCustomized || OrderCustomized || DescriptionCustomized || TagsCustomized)
            {
                IndexProperty.ForwardInstance = new IndexProperty();
                IndexProperty.ForwardInstance.IndexPropertyID = EditIndexProperty.IndexPropertyID;
                IndexProperty.SpecSourceName = IndexProperty.DefaultSourceName;
                if (PropertyIDCustomized)
                {
                    IndexProperty.ForwardInstance.PropertyID = EditIndexProperty.PropertyID;
                }
                if (OrderCustomized)
                {
                    IndexProperty.ForwardInstance.Order = EditIndexProperty.Order;
                }
                if (DescriptionCustomized)
                {
                    IndexProperty.ForwardInstance.Description = EditIndexProperty.Description;
                }
                if (TagsCustomized)
                {
                    IndexProperty.ForwardInstance.Tags = EditIndexProperty.Tags;
                }
            }
            EditIndexProperty.ResetModified(false);
            OnUpdated(this, null);

            // send update back to solution builder
            SendEditIndexPropertyPerformed();
        }