Stanislav Brabec wrote in Wed Nov 16, 2005 at 14:41 +0100: > As a package maintainer, I meet often with two calls for MIME type > virtualization. > > 1) Application uses back-end for file operations. > > E.g. eog can open everything, what can provide gdk-pixbuf-loader > subsystem. > > Using hardwired MIME type list in the eog.desktop is an ugly > work-around. > > 2) Application can open more MIME types using plug-ins. > > E.g. gimp can open image/x-dcraw only if RAW photo plugin is installed. > > Using hardwired MIME type list with MIME types for all plugins and > adding MIME type description XML file to plug-in is an ugly work-around.
> Proposal: > > eog.desktop: > MimeType=virtual/gdk-pixbuf-loader I have just revived my old proposal and tried to look at keywords available in the current spec. I found following ways to define them, changing or not changing spec. Please look at it and let me know, what looks better. First additionally adds sub-class-of virtual/foo to the image MIME type, second one defines new keyword and adds and extends definition of virtual/foo. 1) Keep current spec, change implementation: With current implementation, it is possible to define: /usr/share/mime/packages/gdk-pixbuf.xml: <?xml version="1.0" encoding="UTF-8"?> <mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info";> <mime-type type="image/png"> <sub-class-of type="virtual/gdk-pixbuf-loader"/> </mime-type> </mime-info> It does nearly what we need and surprisingly it works with update-mime-database and does not break MIME type definition (only issues warning). But looking at implementation in Nautilus, it does not exactly, what we expect: Nautilus interprets sub-class MIME types as low priority candidates for opening MIME type - it offers them in sub-menu, but not as default. This behavior seems to be correct (because nobody wants to open SVG in the XML or text editor as a default application). Additionally, it seems that Nautilus offers only applications coming with the first sub-class-of line. We can work-around this problem saying, that virtual/* MIME types are special and candidates offered by this way are good candidates. Pro: No spec change needed Con: Needs change in implementation 2) Define new keyword into spec. Proposed keyword is logically reversed, but not reversed in functionality, I don't propose name "super-class-of", but name "provides": > <?xml version="1.0" encoding="UTF-8"?> > <mime-info > xmlns="http://www.freedesktop.org/standards/shared-mime-info";> > <mime-type type="virtual/gdk-pixbuf-loader"> > <provides type="image/x-dcraw"/> > </mime-type> > </mime-info> Pro: Looks more logical. No "hijacking" of existing definitions. Con: Needs change in spec. Needs change in implementation. -- Best Regards / S pozdravem, Stanislav Brabec software developer --------------------------------------------------------------------- SUSE LINUX, s. r. o. e-mail: [EMAIL PROTECTED] Lihovarská 1060/12 tel: +420 284 028 966 190 00 Praha 9 fax: +420 284 028 951 Czech Republic http://www.suse.cz/ _______________________________________________ xdg mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/xdg
