Iterate through objects in a group

[lexogram]

Hi LiveCoders!

I have 6 graphic objects in a group (dots in a Braille pattern, to be precise).

I can get the number of objects in the group using

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put the number of graphics in group "Pattern"

.

What's the syntax I should use to iterate through each graphic so that I can set its properties?

I've tried...

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repeat for each graphic tGraphic in group "Pattern"
  put the number of tGraphic
end repeat

... but that gives me a script error.

An alternative solution might be to iterate through all the graphics on the card, and ask each if its parent is group "Pattern". What syntax could I use for that?

Thanks in advance,

James

[jmburnod]

Hi lexogram,
I think "the num of controls is one way.
Something like that:

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on mouseUp
  put AllControlInGroup(grMyGroup,"graphic")
end mouseUp

function AllControlInGroup pGroup,pType
   put empty into rAllControlInCr
   repeat with i = 1 to the num of controls of group pGroup
      put i & "," & the  name of control i of group pGroup & "," & cr after rAllControlInCr
   end repeat
   delete char -1 of rAllControlInCd
   if pType <> empty then
      put "*" & pType & "*" into tFilter
      filter rAllControlInCr with tFilter
   end if
   return rAllControlInCr
end AllControlInGroup

Best regards
Jean-Marc

[FourthWorld]

What's the syntax I should use to iterate through each graphic so that I can set its properties?

I've tried...

Code: Select all

repeat for each graphic tGraphic in group "Pattern"
  put the number of tGraphic
end repeat

... but that gives me a script error.

Jean-Marc's function is very complete, but the solution for your handler may possibly be simpler if you could note what the script error was that you encountered.

It may be that simply appending your statement to specify that you're only interested in controls within the group is all you need. Also, we don't yet have a "repeat for each" form for traversing controls (though it would indeed be nice and I believe is on the to-do list), so I'm guessing the error occurs in the repeat statement, yes?

If so, you can modify that to use "repeat with", and with that you automatically get the control number:

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repeat with i = 1 to the number of grcs in group "Pattern"
  put i
end repeat

If you need more specific information about each control you can get its long ID, remembering to specify that you're looking at objects only within the group:

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repeat with i = 1 to the number of grcs in group "Pattern"
  put the long id of grc i of grp "Pattern"
end repeat

[Klaus]

It would be nice if "repeat for each..." would also work this way!

[lexogram]

Thanks to Jean-Marc for his quick and helpful reply. I have got the group script working now.

The script error I get with...

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repeat for each graphic tGraphic in group "Pattern"
  put the number of tGraphic
end repeat

... is:

Script compile error:
Error description: repeat: bad termination condition

It is good to know that a "repeat for each" form for traversing controls is on the To Do list.

[Vanceone]

I was going to post a new topic, but this seems related enough.

Is there a bug with the num of controls? I tried to

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repeat with i = 1 to the num of controls of me
 --stuff
end repeat

inside a group script. It works wonderfully.... except that it is always returning all the controls except the last one. It's like it's not finding that last control. Add a new control to the group, suddenly the previous one is found. So the num of controls is returning all but the last one.

I worked around it by doing a repeat for each line l in the ChildControlID's of me loop instead, but still. Am I imagining things or is that command broken? Livecode 7.0.1 on Mavericks, btw.

[bn]

Hi Vance,

I tried to replicate your setUp: a group with 4 controls and in the group script

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on doCount
   repeat with i = 1 to the number of controls of me
      add 1 to tCount
   end repeat
   put tCount into field "fREs"
end doCount

field "fRes" is outside of the group and the handler is triggered by a button from outside the group.

I always get the correct answer. Using 7.0.1 and Mavericks

Are what are you doing when you do -- stuff, are you deleting?

Kind regards
Bernd

[Vanceone]

Thanks for testing, Bernd.

What I was trying to do was to set the rect of the controls of a background group; adjusting the placement in a resize handler that is called either directly or on preOpenCard. Basically, just laying out the controls. I'm beginning to wonder if I have some deeper issues, because I also cannot set any custom property of a group via the name of a group, only by its id. So for instance I can "Get the uType of group "backgroundControl" but "set the uType of grp "backgroundControl" to "barButton" " does not work either. (it's triggering a "can't find background" error) I have to set the uType of grp id 1725 instead. This is not restricted to just groups; sometimes just setting a custom property on anything is coughing up that same error; a restart seems to fix it.

So I'm not sure what is going on, actually.

This is my current code (that works):

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 local tControlsOfMe
   set the bottom of img "footer.png" of me to (the height of this stack )
   set the top of img "chrome_template_bg.png" of me to the top of this card
   set the top of img "header.png" of me to the top of this card
   put the childControlIDs of me into tControlsOfMe
   repeat for each line l in tControlsOfMe
      if the uType of control id l is "barButton" then
         set the top of control id l to (the top of img "footer.png" of me + 10)
      end if
      
   end repeat

My first try was a repeat with i=1 to the num of controls of me
and it worked great... except that the last control was never actually reached.

[bn]

Hi Vance,

This is not restricted to just groups; sometimes just setting a custom property on anything is coughing up that same error; a restart seems to fix it.

that sounds funny.
When that happens I would copy e.g. just the group to a new clean stack and try the same on this card. Maybe it is a duplicate of a hidden control that lurks somewhere, maybe a missing "of me" in case of groups when addressing them as "control x".
If the same behavior is happening in the new stack/card and you find a recipe to consistently reproduce I would report is as a bug.

I have seen a problem with not resolving a named reference in groups correctly (Bug 10644) but that was reproducible every time and has been fixed in 6.0. And it was a fairly specific condition.
But then there is Bug 14214 where mispelling causes a problem regarding reference and can't find background.

Sorry, I have no idea what is going on.

Kind regards
Bernd