A Composite View is composed of View Items. These are abstract entities, represented in a UI by various controls. The CompositeView exposes its View Items collection via the CompositeView.Items property, and declares additional members, to support the View Item layout functionality. The layout functionality is required to allow automatic generation of Detail Views and provide easy means for layout customization. This functionality allows you to customize a Composite View’s layout at design time (via the Model Editor), at runtime (via the Customization form), and in code. All these customization approaches are detailed in the View Items Layout Customization help topic.