Associating files of a certain extension with an Applescript droplet

[anoved]

Hi, everyone. I posted this question on the Mac OS X Hints forum this morning, so I hope you’ll forgive me for cross-posting it here in an effort to reach more experts.

I have written a simple Applescript droplet as a wrapper for an as-of-yet unreleased command line program. The script implements on run and on open handlers. The run handler just prompts the user to select some files, which are passed to the open handler.

The script works fine when run directly or when files are dropped onto it. I would also like to associate it with files of a certain extension (.rso), so that when these files are double-clicked they are opened with my droplet.

This works fine on a file-by-file basis: I “Get Info” on an .rso file, select “Other” from the “Open With” menu, and select my droplet. Double-clicking the file then opens the droplet, which proceeds as if the file had been dropped on it.

However, if I then click “Change All” to cause any and all .rso files to open in the same fashion, the “Open With” menu unexpectedly reverts to “” and the file no longer opens with my droplet, nor do any others.

It seems as if this is almost possible, since it is possible to associate a single file with the droplet. Does anyone know of a solution? The droplet is saved as an application bundle containing the binary program. Perhaps some tweaks to the bundle’s Info.plist file are necessary to associate it more explicitly with .rso files.

Please let me know if any more details would be useful.

Someone offered a suggestion to specify the rso extension in the property list’s CFBundleDocumentTypes section, but unfortunately it didn’t make a difference. I’ve since provided the following information, too:

I’ve tried mapping .rso files to my droplet with RCDefaultApp, but the assignment doesn’t stick there, either. When I return to the preference panel the default “Other…” item is selected again.

I’ve also tried changing the droplet’s CFBundleSignature in case the generic dplt code confused the “Open With” mechanism, but I’m not sure if that’s so. In any case, it didn’t help.

The messages I am citing are located here: http://forums.macosxhints.com/showthread.php?t=71355

Is anyone familiar with this type of situation? The files I am seeking to associate with the droplet do not have resource forks or traditional type/creator codes, if that has any bearing on the issue.

Thanks for your help,
Jim

[anoved]

I am pleased to report a solution to this problem: I recreated the droplet using Xcode’s Applescript Studio instead of the Script Editor. The resulting droplet application can successfully be set to open all files of a given extension. Just a little tweaking is necessary to obtain the the same behavior as a Script Editor droplet (namely, moving the on run code to on idle and adding quit statements).

[Bruce_Phillips]

It works for me with an AppleScript app bundle (from Script Editor, not Xcode). I removed the CFBundleTypeOSTypes array, and then I set the first element of the CFBundleTypeExtensions array to the desired extension.