Extension:BreadCrumbs2

The BreadCrumbs2 extension generates "breadcrumbs" to help users navigate around your wiki (assuming it has a structure suitable for navigation). Breadcrumbs inserts a single line navigation string before a page's content. A sample breadcrumb for this page is shown in pale yellow above.

For each page the extension can use the categories and/or namespace to:


 * 1) Insert a single line navigation string before a page's content
 * 2) Highlight the active sidebar link and/or tab
 * 3) Change the site logo


 * Breadcrumbs use a single line of text to show a page's location in the site hierarchy... Breadcrumbs have always been a secondary navigation aid... All that breadcrumbs do is make it easier for users to move around the site, assuming its content and overall structure make sense.

BreadCrumbs2 is especially useful with skins like GuMax that display the navigation bar as a row of tabs at the top of the page instead of the Discussion/Edit/History tools.

Usage
The breadcrumb data is stored in a page in the MediaWiki namespace,. To access the page, either enter "MediaWiki:Breadcrumbs" into the search box on your wiki and click the search icon, or copy and paste the link  into a page, then open and edit. The contents are formatted as a wikitext list, with one line per breadcrumb option:

* category name @ breadcrumb wikitext @ tab name @ site logo

Extra blanks between parameters are ignored.

Navigation
The extension inserts a single line navigation string before a page's contents.

For example,

Generates the following breadcrumb for this page:

Note that BreadCrumbs2 uses the first match with the current page's namespace or one of the page's categories. For example, if the Breadcrumbs page contains:

The breadcrumbs for this page would be MediaWiki.org > Extensions > Navigation > BreadCrumbs2 and not MediaWiki.org > Extensions > User interface > BreadCrumbs2 because the Navigation line comes first.

Sidebar
The active link in the navigation sidebar can be highlighted using the tab name parameter, if specified. This is especially useful with skins like GuMax that display the navigation bar as a row of tabs at the top of the page instead of the Discussion/Edit/History tools.

BreadCrumbs2 automatically detects and uses the dynamic sidebar generated by DynamicSkin-based skins.


 * Note: The tab name is compared to the actual text displayed in the sidebar, so it is not language-independent.

Site logo
If the site logo parameter is specified, an alternate image file is used instead of the site default. The path to this image is relative to the root of your wiki.


 * Note: Use this feature with caution so that it doesn't interfere with your site's usability. Subtle changes are good, but dramatic changes can be confusing. If your site needs significantly different look and feel between sections, consider using namespaces and namespace-specific styles and/or DynamicSkin.

Download
You can download the extension code, in .tar.gz format, via Special:ExtensionDistributor.

You can also download the code directly via Git from the MediaWiki source code repository. From a command line, you can call the following:

To view the code online, including version history for each file, go.

Configuration
If breadcrumbs are defined for this page, remove the link back to the base page. Defaults to " ". If no breadcrumbs are defined for this page, show nothing. Defaults to " ".

Tips, tricks, and hoops

 * The breadcrumb list in  defines all the categories and subcategories used for navigation.
 * The extension uses the '@' character to delimit parameters instead of '|' as used in MediaWiki:Sidebar. This greatly simplifies the use of conditional templates in the breadcrumb list.


 * If some of your users don't like the breadcrumbs, they can hide it with some CSS (see Manual:$wgAllowUserCss):

Technical details
The breadcrumbs are built from the data page as follows:
 * 1) The string '@@@' is stripped from the text to be replaced with '@' before output (since the '@' character is used as a delimiter)
 * 2) Pseudo-variables of the form @@VAR@@ are evaluated.
 * 3) * @@USERID@@: User ID, blank if anonymous
 * 4) * @@USERGROUPS@@: Comma-delimited list of groups this user belongs to
 * 5) Templates and variables in the text are expanded. You can use parser functions like #if: if installed.
 * 6) The extension scans each line to find the first match with the current page's namespace or one of the page's categories.
 * 7) The remainder of the line is evaluated to set the breadcrumb string, sidebar, and/or logo (see below)