Stack Switching Question

[Richard Gaskin]

simplsol at aol.com wrote:
 >>> Often times I have a button switch stacks in order to retrieve
 >>> data that I need to complete that button's task. In HyperCard
 >>> I could lock the screen, lock the messages, push the card, go
 >>> to the data stack, retrieve the data, pop the card and insert
 >>> the found data. All without displaying the data stack. When I
 >>> do the same thing in Revolution it displays the data stack for
 >>> a flash. Why does that happen, and how do I stop that data
 >>> stack from showing?
 >
 >>  Better still, you don't need to "go" to a stack to retrieve
 >>  data from it. You can just get it:
 >>
 >>   get fld "Whatever" of cd 200 of stack "MyData.rev"
 >
 > I believe stack "MyData.rev" would have to be open already in order to
 > get fld "Whatever".

I used the file name form to illustrate another difference between HC 
and Rev:  while you would indeed need to open a stack in HC in order to 
get stuff out of it, in Rev you can get property values of objects in 
unopened stacks.  When you do that the engine reads the file into memory 
to access what's being requested; if the stack has been accessed before 
it'll stay in memory (unless you turn on the stack's destroyStack 
property), so subsequent accesses will be lightning fast.

--
  Richard Gaskin
  Managing Editor, revJournal
  _______________________________________________________
  Rev tips, tutorials and more: http://www.revJournal.com