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Now, suppose that you attach the aspect adapter to an instance of the
ViewSubclass class, noting that the ViewSubclass class has an
update: method defined in Segment 810.
Workspace
V := ViewSubclass new.
V model: A.
Now, if you change the value of the fCalories variable in the food,
via an fCalories: message, the view is notified by way of the
attached aspect adapter, and the view obtains the current value of the
fCalories instance variable through
that same aspect adapter:
Workspace F fCalories: 27. Transcript Sample viewer receiving #value update message Value, determined in viewer, is 27
Thus, fCalories: sends changed: to
the food instance, which sends update: to the aspect adapter, which
sends update: to the viewer, which sends value back to the
aspect adapter, which sends fCalories to the food instance.