The Weekly Juan #4: "Smalltalk, Direct Manipulation and End User Programming"

Juan Vuletich juan at jvuletich.org
Tue Nov 14 03:02:51 UTC 2006


Hi Andreas,

Andreas Raab escribió:
> Juan Vuletich wrote:
>> It seems I wasn't clear (again). It is not that I don't want to 
>> discuss these items with you. What happens is that Andreas says 
>> strong and polemic opnions. I actually started to write all the 
>> things I don't agree with in that interview. But I don't think that 
>> would be polite. Perhaps if Andreas asked for other's opinions on his 
>> words...
>
> Sure, go for it ;-)
For example, I don't agree at all with "Morphic is a wonderful 
architecture as far as direct manipulation is involved but it's a 
terrible architecture to build reusable systems. Morphic simply doesn't 
have any abstractions and that makes it very hard to build re-usable and 
flexible components."

"Because MVC is a "viewing architecture"... Tweak ... provides a viewing 
architecture similar to MVC." I don't agree with this either. In Tweak, 
a player knows its primary costume. In MVC, one of the key ideas is that 
a view knows its model, but a mode knows nothing about the views on it. 
I believe the viewing architecture to be quite different.

WRT method annotations for event handlers, it seems as if the receiver 
of the message for some object was always the object triggering the 
event. Usually it is not. It could be an owning morph, or the model(if 
the event is from the gui), or the view (if the event is from the 
model). This is also related to the model not knowing about the view in MVC.
>
>> It is enough for me to say that Morphic is great for building 
>> abstractions, allows separation of view and model (but does not 
>> enforce it), and I don't see any need for a different architecture.
>
> I'm curious how you come to this conclusion. In particular considering 
> that Morphic has no theory of viewing (the Pluggable* classes for 
> example were added as an afterthought to support apps written for MVC 
> and have nothing to do with what I would consider a "true Morphic app").
>
> Cheers,
>   - Andreas
ScorePlayerMorph and EnvelopeEditorMorph are good examples of views on a 
model, in the classic MVC idea of the view knowing about the model, and 
the model not knowing about the view. I don't see the need for a "theory 
of viewing". It is enough with separating the view and model 
responsibilities, and triggering events, just as in MVC.

Cheers,
Juan Vuletich



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