Recursion example stack

[David Burgun]

Hi All,

Following on from Martin, I write something that I think might be on 
interest that uses recursion in a less obvious way. I use it to 
handle Card/Group updates in a "standard" manner. This makes the 
script much more reusuable. In your mainStack or a Utility stack, add 
the following function:

function UtilStackUpdateGroup theOwner
   local myIndex

   --
   --  Update all Groups that need to be Updated
   --
   repeat with myIndex = 1 to number of groups in theOwner
     if word 1 of the name of group myIndex of theOwner = "Group" then
       if the long owner of group myIndex of theOwner = theOwner then
         if the script of group myIndex of theOwner contains "GroupUpdate" then
           send "GroupUpdate" to group myIndex of theOwner
         end if
       end if
     end if
   end repeat

   repeat with myIndex = 1 to number of controls in theOwner
     if word 1 of the name of control myIndex of theOwner <> "Group" then
       if the long owner of control myIndex of theOwner = theOwner then
         if the script of control myIndex of theOwner contains 
"ControlUpdate" then
           send "ControlUpdate" to control myIndex of theOwner
         end if
       end if
     end if
   end repeat
end UtilStackUpdateGroup

This loops thru each Group in the Object passed to it (Card or Group 
in this case) and then thru each Control on the Object passed to it. 
An update is triggered when the user does something that affects 
another Object(s) on the card, for example for a check box, you'd do 
this:

on mouseUp
set the cpCheckBoxFlag of this card to the hilight of me
send "CardUpdate" to this card
end mouseUp

The CardUpdate function, just does this:

on CardUpdate
   get UtilStackUpdateGroup(the long name of me)
end CardUpdate

On each group you want to be updated, add this (this will update all 
Sub-Groups) in this Group:

on GroupUpdate
   get UtilStackUpdateGroup(the long name of me)
end GroupUpdate

On each control you want updated, do this (this is a terminal node 
and so ends the current recursion which will bubble back up to the 
top again):

on ControlUpdate
if the cpCheckBoxFlag of this card is true then
set the borderColor of me to red
else
set the borderColor of me to green
end if
end ControlUpdate

Add a ControlUpdate to each control you want to update, but only use 
Custom Properties to pass information.

The cool thing about this is you never need to refer to any 
control/group name, which means you can paste groups into other stack 
and not worry about the names of objects, therefore making the whole 
process much more standard and easilly moved. All have to do is to 
make the the Custom Properties are setup correctly. You just define 
which Custiom Properties are used as input and outputs and hey presto 
- It works!

This describes the update path, I do the same for initialization and 
Stack resizing, e.g. CardInitialize, GroupInitialize etc.

All the Best
Dave