Provide "alternate stylesheets"

[anonymous]

It would be great if Trac provided alternate stylesheets in its generated html. (I didn't see anything similar in 0.9.4)

Here's a patch against trac-0.9.2/trac/web/chrome.py:

--- chrome.py.orig      2005-12-05 13:20:16.000000000 -0500
+++ chrome.py   2006-03-14 10:42:59.000000000 -0500
@@ -51,6 +51,15 @@
         href = Href(req.cgi_location).chrome
     add_link(req, 'stylesheet', href(filename), mimetype=mimetype)
 
+def add_alt_stylesheet(req, filename, mimetype='text/css'):
+       """Add a linke to an alternate stylesheet
+       """
+       if filename.startswith('common/') and 'htdocs_location' in req.hdf:
+               href = Href(req.hdf['htdocs_location'])
+               filename = filename[7:]
+       else:
+               href = Href(req.cgi_location).chrome
+       add_link(req, 'alternate stylesheet', href(filename), title='alt style', mimetype=mimetype)
 
 class INavigationContributor(Interface):
     """Extension point interface for components that contribute items to the
@@ -212,6 +221,7 @@
         add_link(req, 'search', self.env.href.search())
         add_link(req, 'help', self.env.href.wiki('TracGuide'))
         add_stylesheet(req, 'common/css/trac.css')
+        add_alt_stylesheet(req, 'common/css/trac-alt.css')
         icon = self.config.get('project', 'icon')
         if icon:
             if not icon.startswith('/') and icon.find('://') == -1:

[Emmanuel Blot]

Alternate style sheets can be activated using and customizing the site_css.cs file.

[anonymous]

Wrong. site_css.cs provides for a project specific style sheet. It does not provide an alternate style sheet as defined in HTML 4 / XHTML ​standard. Alternate style sheets are provided by content authors and allow for user selection via their browser. In order for an author to provide an alternate stylesheet, it must be linked to the document in a particularly <link> tag in the html. (Which in the case of Trac requires a patch like submitted above.)

[Emmanuel Blot]

Ok, you're right, I misundertood the ticket description.

[anonymous]

My fault. My initial description wasn't descriptive enough.

Thinking about it a bit more, this is a "nice to have feature". But, for this particular thing, where would one draw the line? One alternate stylesheet? Three? Twelve? Maybe, like in the patch, just add one, then in the docs (FAQ?) add a pointer to were to make the changes if the Trac admin wants more alternate stylesheets.

[coderanger]

Sounds like it would be good to have as an option in trac.ini, just have a :-seperated list of files.

[Christopher Lenz]

You still can add alternative style sheets using site_css.cs:

</style>
<link rel="alternate stylesheet" title="Cold Turkey" href="/path/to/stylesheet" type="text/css" />
<style type="text/css">

The hacky part is that you need to close and open the style tag to break out of the one contained in the master template.

[Christian Boos]

The above trick probably doesn't apply anymore, but now with Genshi it's possible to make more complex manipulations in the site.html file, see TracInterfaceCustomization#Trac0.11andabove.