Re: Idle Help
Re: Idle Help
- Subject: Re: Idle Help
- From: Byron Peterson <email@hidden>
- Date: Wed, 6 Dec 2000 19:38:27 -0700
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Byron Peterson wrote:
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> How do I pass variables from the 'run' section to the 'idle' section
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> without using 'global' or 'property' statements.
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> ie.
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> on run
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> set test to "Hello World!"
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> end run
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> on idle
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> display dialog test
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> return 10
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> end idle
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You don't. I realize that you may have had "Globals Are Bad" burned
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into your brain in an introductory programming course, but the reality
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is that sometimes there's no other way. This is one of those times.
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The difficulty is that "run" and "idle" are independent entry points
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into your script that are called from the outside, i.e., the applet
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shell. In order to share information between them, you have to put it
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somewhere both handlers can see, and that means a global or property of
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some sort.
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If it really bothers you, you can compartmentalize the offending globals
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by putting them inside a script object, like this:
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script messages
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property hello : ""
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end script
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on run
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set hello of messages to "Hello world!"
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end
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on idle
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display dialog hello of messages
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end
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If there's only one global, this technique is mostly a waste of time,
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but if you have lots, and they fall into clear groups, then it's a good
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way to keep them separate.
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--Chris Nebel
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AppleScript Engineering
OK, let me break down the problem I am having and maybe you can help.
I have written a script to change the desktop picture at a set
interval. The script has support for two monitors and the ability to
alternate back and fourth between them. I read the picture files
from a folder (as well as from sub folders) into a list (this happens
during the run stage). I then get a random number (1 to total number
of items in the list) and display that image on either monitor 1 or 2
(whichever is next) using the appearance manager during the idle
stage. After I select an image, I remove it from the list (so that
the same picture won't be displayed again until all pictures have
been displayed). After the list reaches 0, I then re-read the
picture files back into the list and start the process over. The
problem I am having is it isn't random at all. After a computer
restart, it starts with the same picture every time,then goes to the
same second picture and so fourth. I have looked and looked for the
problem but it doesn't appear to be how I get the random number.
Below is the code that gets the random number.
set listTotal to the count of desktopPictures
set randomNumber to random number listTotal from 1 to listTotal
The only thing that I have found is a brief comment somewhere (I
don't remember where) that states the variables carry their values
across restarts when you use global or property settings. I am new
to applescript and really don't understand how (and when) to use
global variables or property variables and exactly what there overall
effect is. If anybody can give me some good insight, I would
appreciate it.
Thanks,
BJ
| References: | |
| | >Idle Help (From: Byron Peterson <email@hidden>) |
| | >Re: Idle Help (From: Chris Nebel <email@hidden>) |