Heads Up For HyperCard Stack Converters

Rob Cozens rcozens at pon.net
Thu Oct 24 10:33:02 CDT 2002


Hi All,

Did you know that, without manual intervention, Revolution stacks 
created from HyperCard stacks will work differently than native RR 
stacks?

In converting OenoLog from HyperCard to Revolution I decided to do a 
redesign instead of a straight conversion.  However, I did not want 
to lose the positioning of most controls or the contents of fields; 
so I used HC PowerTools to save all stack scripts to a text file and 
removed the scripts, AddColor database, and other unwanted items from 
the stack before opening & saving it with RunRev.  I was unknowingly 
setting myself up for VERY esoteric potential problems, and only 
accidentally became aware when I found this in the Rev Dictionary:

>>
dynamicPaths

If a stack's dynamicPaths property is true, when a handler in that 
stack goes to a card other than the original card, that card's 
message path is inserted into the message path as long as the handler 
is on that card.

If the dynamicPaths is false, the message path does not change even 
when a handler visits another card.

The dynamicPaths property of stacks imported from HyperCard is set to 
true by default.
<<

and

>>
HCAddressing

When you open a HyperCard stack and convert it to a Revolution stack, 
the new stack's HCAddressing property is set to true.

If the HCAddressing property is set to true, expressions in the 
stack's scripts that refer to fields without specifying card or 
background are assumed to refer to grouped controls, and expressions 
that refer to other control types are assumed to refer to card 
controls...

If the HCAddressing property is false, expressions that refer to 
fields or buttons without specifying card or background are assumed 
to refer to all fields or buttons.
<<

Can you imagine trying to debug problems in converted HC stacks if 
one is unaware of these differences?

Can anyone tell me if there are other properties that differ between 
converted HC & native RR stacks?  [There is an HCStack property; but 
it is read-only and does not directly alter stack behavior.]
-- 

Rob Cozens
CCW, Serendipity Software Company
http://www.oenolog.com/who.htm

"And I, which was two fooles, do so grow three;
Who are a little wise, the best fooles bee."

from "The Triple Foole" by John Donne (1572-1631)



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