Creating a reusable object - Part 2

J. Landman Gay jacque at
Thu Aug 9 16:37:29 EDT 2012

On 8/8/12 11:37 PM, Mark Smith wrote:
> I haven't played with back scripts so I'm not sure how I would
> get that working (or how different it would be from just having a stack
> script... but feel free to enlighten me... please!)

Backscripts and frontscripts are just scripts in the message hierarchy 
that don't need to be attached to any object. They are stored in an 
object so they will be saved with the stackfile, but once inserted, the 
object isn't referenced at all. Frontscripts receive messages before 
your stack does. Backscripts receive messages after everything else 
(after the stack script.)

Inserted scripts are global; that is, they will be in the message path 
of any stack. If your backscript is useful only for one particular 
stack, it's customary (and polite) to insert it when that stack opens 
and remove it when the stack closes.

Since you're interested in the resizestack handler, you could create a 
button with a script that has a resizestack handler in it. At some point 
before it's needed a script should:

   insert script of btn x into back

When the engine sends a resizeStack message, it will go through the 
message path normally and if there is no handler in the card or stack to 
catch it, the backscript will catch it and execute its commands.

Since you want to respond only to certain cards, I'd mark those cards 
somehow, with a custom property probably, and have the handler check to 
see if it should act. Although in this situation your group method may 
actually be easier, since the handler will only fire on cards that have 
the group. I tend to avoid excess objects whenever possible so I'd 
probably go for the backscript, but that's mostly just a style preference.

Jacqueline Landman Gay         |     jacque at
HyperActive Software           |

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