What is the proper way to program with Morphic?

David N. Smith (IBM) dnsmith at watson.ibm.com
Mon Nov 8 23:46:28 UTC 1999


At 13:27 -0500 11/2/99, David N. Smith \(IBM\) wrote:
>Can someone point me to an example or two that shows the proper way 
>to program in morphic? There are lots of examples, but it's not 
>clear which are true morphic ways, which have some MVC left by 
>accident, which are written by someone exploring things, and which 
>do it the 'right' way.
>
>There are a few plugable morphic classes; are these for 
>compatibility with MVC applications only?
>
>I have written one morphic application, a client, that works fine 
>but I'm not at all sure if the program structure is at all what it 
>should be.

Well, I've found a frequent coding technique that bothers me: using 
#initialize to open the morph.

This makes it impossible to subclass the morphic class and change 
existing defaults since there is no possible way to send #initialize 
to super: do it before and the morph is open with the parents 
defaults, and do it after the parent overrides the changed 
initializations.

I first found this a problem when I wanted to change the default 
colors in the tile game. I found some were too vivid and made it hard 
to 'see' some others. I checked a dozen other places and found the 
same coding technique.

Is this a standard morph coding technique? If so, why? Couldn't the 
opening code be put into an #open method which is always sent just 
after #initialize?

Dave
_______________________________
David N. Smith
IBM T J Watson Research Center
Hawthorne, NY
_______________________________
Any opinions or recommendations
herein are those of the author
and not of his employer.





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