A primitive is an EiffelVision 2 widget that may not contain other widgets. Primitives may be placed in containers, but a primitive widget may not contain any child widgets. Some examples of primitives are EV_BUTTON and EV_LABEL. All EiffelVision 2 primitives inherit from EV_PRIMITIVE.
Features of a Primitive
All primitives inherit from EV_TOOLTIPABLE and therefore may have tooltips assigned to them. They all inherit many features from EV_WIDGET. Each descendent of EV_PRIMITIVE will typically have many features specific to its type. For example, EV_SEPARATOR has no extra features, but EV_LABEL has features for modifying the current font and text to be displayed.