Re: "help" URLs
Re: "help" URLs
- Subject: Re: "help" URLs
- From: Jessica Kahn <email@hidden>
- Date: Fri, 3 Aug 2001 18:22:45 -0700
Ondra,
If I understand your question correctly, you can, as an application
developer, claim that you are the a handler for a given URL scheme in a
couple of ways.
Help Viewer claims itself as Apple's default handler for help: URLs
using some keys in its Info.plist file. Because third parties probably
wouldn't claim to be Apple's default anything, you'd just specify that
you are capable of handling a given URL type. See
<
http://gemma.apple.com/techpubs/macosx/SystemOverview/SystemOverview/SoftwareConfig/
iInformation_perty_Lists.html> for more information. In particular, look
at the bits that talk about CFBundleDocumentTypes and CFBundleURLTypes.
The LaunchServices APIs that allow you to specify a URL to open will
choose a handler application based on what apps registered for that URL
scheme. Users can override LaunchServices' default choice by setting
handlers for particular document (and I think, URL) types in the
Finder's UI.
Don't quote me on this stuff though; I'm neither a Finder nor a
LaunchServices engineer.
Pre-Cocoa, back on Mac OS 9.x and before, an application could register
itself as the handler for a particular URL scheme using Internet Config.
You can still use Internet Config on X; it's a part of Carbon. I believe
that, to a large extent, Internet Config just calls through to
LaunchServices these days, but I'm not sure if their databases of helper
apps are one and the same, are separate but synced up, or are unrelated.
Browsers on X, or really any application responsible for handling URLs,
should probably ship them off through LaunchServices to make sure the
right recipient application is chosen. Again, in the pre-X days,
Internet Config served this same purpose.
Hope this helps to explain things.
--Jessica
On Friday, August 3, 2001, at 05:41 PM, Ondra Cada wrote:
Jessica,
Jessica Kahn (JK) wrote at Fri, 3 Aug 2001 13:43:07 -0700:
JK> If a browser isn't handling help: URLs properly, it's that
individual
JK> browser's bug. Help Viewer registers on all Mac OS X systems as the
JK> default handler for URLs with the "help" scheme, and so a
well-behaved
JK> browser should be able to ship them off to Help Viewer via any of
the
JK> system-supplied mechanisms for doing so (i.e. LaunchServices,
JK> InternetConfig, etc.).
Uh, that looks like some feature which I've never appreciated: could you
please point me to a piece of documentation which describes how to
register
an application's service for a specific URL scheme? None features which
I can
remember (like Filtering Services, standard application document
types/extensions, etc., not even generic Services) seem to fit that?
---
Ondra Cada
OCSoftware: email@hidden http://www.ocs.cz
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