StateVarView(3U) InterViews Reference Manual StateVarView(3U)
NAME
StateVarView - state variable view base class
SYNOPSIS
#include <Unidraw/stateview.h>
DESCRIPTION
StateVarView is the base class for state variable views. State variable views provide a graphical interface to examining and potentially
modifying a state variable subject. The StateVarView base class is an abstract class derived from MonoScene. Like MonoScene, the State-
VarView class is not instantiated; instead, subclasses add state and behavior appropriate for displaying and editing their subject. Like
other MonoScene subclasses, StateVarView subclasses use an interactor composition to define their appearance.
PUBLIC OPERATIONS
virtual void Update()
Update the state variable view in response to a change in state it depends on (typically the subject's). This operation does not
normally need redefinition if Init and Stale (described below) are redefined.
PROTECTED OPERATIONS
StateVarView(StateVar*)
Subclass constructors normally take an instance of the corresponding subject as an argument. The base class constructor automati-
cally attaches the view to the subject.
virtual void Init()
Initialize the view based on information in the subject. Subclasses redefine this operation according to their semantics; it does
nothing by default.
virtual boolean Stale()
Return whether the view is in any way inconsistent with its subject. This operation always returns true by default; subclasses can
redefine it to make a more discerning decision.
SEE ALSO
MonoScene(3I), StateVar(3U)
Unidraw 6 August 1990 StateVarView(3U)