Destroying cloned stacks

J. Landman Gay jacque at hyperactivesw.com
Sun Feb 21 22:11:10 CST 2010


Jeffrey Massung wrote:

> Main Stack:
> 
> on newDocument
>    clone stack "Document"
> 
>    ## setup document stack here...
> 
>    go to it
> end newDocument
> 
> 
> Document stack:
> 
> on closeStack
>    destroy this stack
 > end closeStack

I didn't even know that syntax worked. Apparently it works pretty well. 
Too well.

Anyway, what it looks like you've hit is the defaultstack issue. If your 
main stack happens to be the defaultstack when the handler runs, "this" 
stack is going to refer to your mainstack.

> So, my questions:
> 
> 1. Am I going about creating a document stack the right way?

Yes. Though I usually set up all the common properties, like 
destroystack, in the template before I save it into the main stackfile; 
that way I don't have to worry about it, all clones will have those 
properties. If you do that, all you'd have to do is trap 
closeStackRequest for any cleanup work when the user clicks the close 
box. The stack would not stay in RAM when allowed to close.

> 2. How can I nuke clones and not the primary document stack?

I sometimes name my clones with an identifying tag, like "clone 1", 
"clone 2", etc. and then set the stack's label (also called "title") to 
whatever the user should see as the window title. It makes testing for 
the right stack easier.

The IDE uses this a lot to force commands to act on the right stack:

   set the defaultstack to the topstack

Which will only work in this case if your clones really are the top 
stack. Or you can test for a custom name tag to see if you're in the 
right place:

   if the short name of this stack contains "clone" then...

Or test the inverse:

   if the short name of this stack is not "myMainstack" then...

Perhaps easiest, if your closestack handler is in the stack script, then 
the term "me" will refer to that stack. So in your clones, you could 
also say

   close me

Or:

   set the destroystack of me to true
   close me

In no case would "me" ever be your main stack, because "me" is the 
object containing the running handler. Using "me" can sometimes be the 
simplest solution, provided it's feasible to put your handler in the 
stack script. Sometimes that can cause interference in other ways, but 
we won't go there today. You've been through enough.

BTW, there is an auto-save utility in Rev's plugins menu. Just tell it 
how often to save, and leave it open.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com



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