Arrays and Custom Props

Jim Ault JimAultWins at yahoo.com
Sat Feb 14 10:45:29 CST 2009


I think people get a little confused when they think of Hypercard and how it
always saved changes to the hard drive as they occurred.  The key is that
Hypercard stacks are like spreadsheets or word processing documents in that
you needed the app Hypercard installed on your Mac, and it was free.  Most
of the time it was already installed on the Mac when purchased.  There was
the issue of multiple versions through the years.

Basically a Rev app could work the same way as the Hypercard app.  On launch
you would give the user a choice of opening an existing 'document' or stack
or create a new one.  A spreadsheet .xls file is just a bunch of
gobbledy-gook and data that requires the correct version of an app to use.

Standalones do the same thing... save lots of data to files on a hard drive
and manage the changes in formatting between versions.  "Are you sure you
want to update the format of your document to V3.4.5.6?"   "Save as
Photoshop, Jpeg, Compuserve Gif, Tiff...."

Your choice could be to do like Hypercard and Filemaker... save to disk
after every change so the user never had to make that step, thus immediate
persistence.

The app, of course, does not change, just the files in its universe, even if
they are on the network, somewhere out there.

As far as custom properties, recall that in my first email I mentioned that
you could store a whole stack in a custom prop.. well, this is one way you
could store a "New Stack" that opens for the user, just like Excel or Word,
or a "New card" that was not already in the user stack, or a "New Group",
etc, etc.  This way, a new stack does not have to have all of the parts that
the app does, and those are only installed when needed from the mother ship.

I have not looked, but there are probably some videos and help files on
bundling 'resources' with a standalone since so many Rev apps have been
created and distributed by pros on this list.  My apps are simple,
functional, and go to private clients so I am not well-versed in wide
distribution.

Hope this makes your weekend a bit calmer.  Think about it as traveling the
oceans as millions of others do.. in a boat on the surface.  Very few people
ever use a submarine.  Revolution builds boats.

Jim Ault
Las Vegas

On 2/13/09 4:42 PM, "Richard Gaskin" <ambassador at fourthworld.com> wrote:

> Bob Sneidar wrote:
> 
>> WHOA THERE TONTO! I thought the whole idea to properties was
>> persistence?? That means that I cannot save, for instance, the
>> database settings a user entered? I have to create an external file
>> for all of that? And so many card and object properties in my app
>> DEPEND on persistence through runtime. This means that I have to put a
>> kabosh on the whole project!
> 
> You're no worse off than any other application developer:  Windows and
> Linux have never allowed applications to modify themselves at runtime,
> and even Mac OS only allowed this back when it still put executable code
> in the resource fork (though under OS X any app can store files in the
> bundle).
> 
> This article at revJournal may be helpful:
> 
> Saving data in Revolution standalones
> by Sarah Reichelt
> <http://www.revjournal.com/tutorials/saving_data_in_revolution.html>
> 
> 
> --
>   Richard Gaskin
>   Fourth World
>   Revolution training and consulting: http://www.fourthworld.com
>   Webzine for Rev developers: http://www.revjournal.com
> _______________________________________________
> use-revolution mailing list
> use-revolution at lists.runrev.com
> Please visit this url to subscribe, unsubscribe and manage your subscription
> preferences:
> http://lists.runrev.com/mailman/listinfo/use-revolution





More information about the use-livecode mailing list