How do I scan all the objects on a card?

[Graham Samuel]

On  Tue, 11 Feb 2003 20:03:30 -0800 "Jeanne A. E. DeVoto" 
<jeanne at runrev.com> wrote:
>
>At 1:14 AM -0800 2/11/03, Graham Samuel wrote:
>[...] But what about
>  >my objection from the transcript dictionary (the implication that the
>>numbers aren't unique?)
>
>Graham, can you be more specific about what gave you this idea? I'd like to
>correct it, of course, if there's a particular statement that's unclear or
>misleading....
>

Well, I guess I put 2 and 2 together and made 5, but I would be 
surprised if I was the only one...

If you have a card with a lot of objects on it (well, more than one 
will do), and you look at the properties of any object via the 
Development Environment, you will see a set of four buttons for 
changing the object's layer - 'send to back', 'move backward', 'move 
forward' and 'send to front'. My mental model of the card was that 
the layers could be shared, so that one imagines 'sent to back' 
objects like the backdrop in a theatre, and foreground objects like 
props or actors, some sets of whom might be exactly the same distance 
from the front of the stage.

With this mental model it's natural to assume that several objects 
could be **at the same level** at the same time. Indeed, this does 
happen on the Mac, I believe, where drawing programs based on 
QuickDraw can (for example) bring a whole bunch of objects to the 
front in one action. So I reasoned that layer numbers could not be 
unique. Of course the docs never say this, although the glossary 
entry for 'layer' could be interpreted that way:

"The position of a control relative to the front and back; the order 
in which controls are stacked on the card"

Now that I've looked into it more thoroughly of course I see that 
Revolution doesn't have 'my' model, although I have not yet worked 
out all the consequences (for example, a group will contain objects 
which by definition will all be on separate layers - what happens 
when I send the whole group to the back?).

I'm sorry that people like me keep banging on about misconceptions 
we've somehow picked up on the way and then seem to be blaming them 
on the documentation. I do feel the docs are well done and therefore 
don't want to appear negative. Maybe it helps to see that different 
people approach issues from a different angle sometimes.

Graham
-- 
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          Graham Samuel / The Living Fossil Co. / UK & France