Morphic Docs on swiki

Russell Swan swan at
Sat Mar 18 21:07:36 UTC 2000


Thanks very much for the Morphic Tutorial.. They are very informative and
its great to get some documentation on Morphic. There are some parts of
Morphic that I am quite fuzzy about, and I hope you address these in later

Specifically, I'm confused about models in Morphic. My understanding of
models in Smalltalk and MVC is that a model contains the logic of the
application and is kept separate from the interface. Interface elements
are registered with a model by sending them the #model: message. Models
communicate by sending themselves the #changed message, which causes an
#update: message to get sent to every dependent.

Morphics are graphical objects and they appear on the screen. I would
expect their state, appearance and behavior to be controlled by messages
sent from their model. In the counter application example on the Swiki,
its done that way, with Counter and CounterApplication both being
subclasses of Model. However, most morphics do not understand #model:
#model: is defined in the MorphicModel class, and slots are defined along
with models. Most of the subclasses, which are the most of the morphs that
understand #model:, are PluggableXXXMorphs.

What is the relation between Morphic, Model, and MorphicModel? What is a
slot and what is it used for? What are PluggableXXXMorphs - what makes
them Pluggable, how are they defined, and how are they used?

I hope you can answer some of these questions in one of your future docs.

-Russell Swan

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