Lazy Loading?

Hi There,

Environment : SL3, VS2008, DevForce 5.2.6

We have a basic model that seems to be lazy loading a nested collection. In a nutshell we have a Product that has a collection of colors. We've setup a basic SL input form to allow customers the ability to choose a Product from a combobox. In turn, we filter another combo box with available colors for that product. Problem is, the first time you select a product the color collection has no items in it. The second and subsequent time(s) the colors appear fine.

Has anyone else experience this behaviour? It's appears as though the colors are lazily loaded?

Regards
Marcus

Thanks for the response. Please see details below;


public class ProductList : ObservableCollection<Product>
    {
        public ProductList()
        {
             ((App)App.Current).Manager.ExecuteQueryAsync(((App)App.Current).Manager.Products, GotProducts, null);
        }

        private void GotProducts(EntityFetchedEventArgs args)
        {
            if (args.Error != null)
            {
                //WriteMessage(args.Error.Message);
            }
            else
            {
                foreach (Product product in args.Result)
                {
                    this.Add(product);
                }
            }
        }

      
    }

* Note : When each product is added the the collection in the foreach loop, the Product.Colors have no items, is this normal behaviour?

<data:DataGrid.Columns>
                                <!-- Product Combo -->
                                <data:DataGridTemplateColumn Header="Product/Style">
                                    <data:DataGridTemplateColumn.CellEditingTemplate>
                                        <DataTemplate>
                                            <ComboBox x:Name="cboProduct" ItemsSource="{StaticResource Products}" DisplayMemberPath="Description" SelectedItem="{Binding Source={StaticResource SalesOrderVM}, Path=SelectedProduct, Mode=TwoWay}"></ComboBox>
                                        </DataTemplate>
                                    </data:DataGridTemplateColumn.CellEditingTemplate>
                                </data:DataGridTemplateColumn>

Upon choosing a Product from the ComboBox, the colors collection has no items. Subsequent selection shows colors where appropriate. It's like the Async fetch takes a while to retrieve?

Please let me know if you require more information.

Regards
Marcus