Newbie

Richard Gaskin ambassador at fourthworld.com
Tue Feb 10 11:33:22 EST 2009


DunbarX wrote:

> It was just that, as Mark said, you have to already have at least one bg to 
> set the editbg property at all. I thought I would set it and then do some work. 
>   Don't go "true" without it. 

Yep.  Unlike HC, which always has one background on every card, Rev can 
have any number of backgrounds, or none, as you wish.

So to edit a background it must first exist. ;)

When importing HC stacks, the backgrounds come along for the ride so in 
conversion it's rarely an issue.

When developing fresh in Rev, however, the more flexible object model 
carries the small price of creating the objects, like backgrounds, you 
want to modify.


> Incidentally, the property is not saved if one closes the stack and then 
> reopens it; it defaults to "false" (saving the stack makes no difference). So it 
> is not, in my thinking, much of a property, more like a temporary tool.
> 
> This last disconcerted me; I could accept that I did not understand the 
> limitation. I was upset that my idea of what a property was is now useless. Are 
> most stack properties like that?

Properties come in many flavors.  Some are persistent, some are reset to 
defaults between sessions, some are read-only.

Most object properties are persistent, but there are a few properties 
which aren't, like editBackground.

The editBackground property governs an interaction mode, and like "tool" 
and most (all?) global properties the mode for a given session always 
defaults to a single state when a new session begins.

I've just added a request to the RQCC to add a note to the Dictionary 
entry for editBackground that it isn't persistent between session:
<http://quality.runrev.com/qacenter/show_bug.cgi?id=7701>

If memory serves, this behavior is similar to HyperCard, in which if you 
were editing a background in HC and then quit, launching HC again and 
opening the stack would bring you back to the "normal" 
(non-background-editing) mode.


> Newbies do a lot of whining.

You should have seen my early posts; they make some of the most ardent 
whining in more recent years seem angelic. :)

When I first started with Rev (it was still "MetaCard" back then) I came 
from a strong SuperCard background, so any difference between this new 
engine and the one I was used to I labeled as a mistake.  Fortunately 
Scott Raney (MetaCard's inventor) and Kevin Miller were far more patient 
with me than I was with the engine, and they very helpfully explained 
the "Why" behind the differences (usually due to multi-platform 
considerations).

Over time I've come to prefer how Rev does most things. I hope your 
experience is as fruitful in the long run.  And in the short run at 
least you have us. :)


> I "have" Winkler, Kamins and DeVoto. And I have this list. I need Danny 
> Goodman.

In the Rev world we have Jacque Gay.  Her excellent tutorial on 
migrating to Rev from HC is priceless:
<http://www.hyperactivesw.com/mctutorial/index.html>

I don't know if it addresses this specific issue with backgrounds, but 
there are a great many gems in that, well worth the read.

--
  Richard Gaskin
  Fourth World
  Revolution training and consulting: http://www.fourthworld.com
  Webzine for Rev developers: http://www.revjournal.com



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