Forms and reusable parts have a property called Ancestor. It is used to specify the component from which this component inherits from. "Inheriting" means the component has the same characteristics and contents as its ancestor, for example the same:
By default forms inherit from #PRIM_FORM which is the basic Visual LANSA form. It cannot be modified. However, you can specify any other form as the ancestor of a form.
By default reusable parts inherit from #PRIM_PANEL. It is the basic Visual LANSA panel. You can make the ancestor of a reusable part to be any type of component (except a form), such as a button (#PRIM_PHBN) or a LANSA field. If the reusable part contains only logic (and no visual interface), it is most memory efficient to make its ancestor #PRIM_OBJ.
The Ancestor and other Inheritance-related properties are only visible in the editor when the Show Advanced Features option is selected in the LANSA Settings dialog.