Calling AppleScript Handler from Cocoa Application in PB

jonn8 · August 10, 2003, 10:00pm

I’m building a Cocoa app and I’m very new to Objective-C. I have a library of AppleScript handlers that I would like to call from my Cocoa app passing variable parameters to the various handlers but I’m stumped how to make this work. I understand how to call a script and have it return a value from the explicit run handler but not other handlers and not passing parameters.

Thanks,
Jon

Rob · August 10, 2003, 10:28pm

I don’t know if this works with a Cocoa app (can you use a script to call another script?) but say you have a script with the following handlers.

to add2numbers(n, nn)
	return n + nn
end add2numbers

to mulitply2numbers(n, nn)
	return n * nn
end mulitply2numbers

Now you can load this script and call the various handlers within it.

set foo to load script file "path:to:library"
set multiplied_ to foo's mulitply2numbers(2, 6)
--> 12

set sum_ to foo's add2numbers(2, 1)
--> 3

Is that what you need?

jonn8 · August 10, 2003, 10:44pm

Rob, thanks, but I don’t think that’s what I need. I found this posting online and I think it is more along the lines of what I want to do but I can’t figure out how to make it work (the author didn’t respond to my query even though I promised valuable rewards for some illumination).

Jon

Rob · August 10, 2003, 10:55pm

Ok, I was afraid of that. Sorry I can’t offer more.

– Rob

Rob · August 11, 2003, 4:53am

Jon,

Here’s a post to the applescript-users mailing list that might be helpful.

On Sunday, August 10, 2003, at 1:43 PM, Chris Backas wrote:

The NSAppleScript class has an executeAppleEvent method, which takes
an AppleEventDescriptor as an argument. I’ve seen on the Applescript
side that one makes an event handler something like:

on ()

end

My confusion is, does that single AppleEventDescriptor I pass
encompass both and ? If I want to pass a
list to a handler in an applescript, do I need to declare my own kind
of handler someplace with its own ID, or are there preexisting ones
that I’m meant to utilize?

This question would have been more appropriately asked on
applescript-implementors, but never mind that. You should go read
QA1111, “Calling an Applescript and providing parameters from an
application,” <[url=http://developer.apple.com/qa/qa2001/qa1111.html]http://developer.apple.com/qa/qa2001/qa1111.html[/url] >. It’s
written for C, but shouldn’t be too hard to translate to Obj-C.

The basic point is that an “event” encapsulates both the handler name
and its parameters. The handler you use can be defined one of three
ways:

Define your own handler name and call it with positional parameters,
as in QA1111.

Define terminology for your handler and call it with named
parameters (Folder Actions does this).

Use an existing standard handler, such as “run” or “open”.

As far as how to call them, #1 is illustrated in QA1111. #2 is just
like sending a “normal” Apple event to an application, and #3 is just a
special case of #2. Obviously, using #3 appropriately depends on what
you intend to do in the handler.

–Chris Nebel
Apple Development Tools

jonn8 · August 11, 2003, 1:53pm

Thank, Rob!

Jon

Rob · August 11, 2003, 9:28pm

Jon, I don’t know if you subscribe to the applescript-studio list so here’s something else that popped up today and might be useful.

DocGlue was created as a global data store for all your AppleScript Studio scripts. It can remember values for later, then recall those same values in another script. The download package includes an Objective-C class (doing all the work), an AppleScript library (talking to the Objective-C class), documentation, and a Sample project.

– Rob

jonn8 · August 12, 2003, 12:29am

Rob, thanks for being on the lookout. I don’t subscribe to the list but I do search it (and others) periodically using the excellent and invaluable iList. I’ll take a look at DocGlue and let you know how that goes as well.

Thanks,
Jon

ktam · August 12, 2003, 12:40pm

Thanks for the pointer to iList, a bit quirky at first, but absolutely wonderful. Never again will I have to trawl through those huge text files on the carbon and quicktime lists. It would be good but not quite so necesary if iList could work on these lists as well.

Kevin