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 StateVarView 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 automatically 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)