Extension:TreeAndMenu

The TreeAndMenu extension makes bullet lists into folder trees or dynamic drop-down menus.

The drop-down menu functionality uses Son of Suckerfish which is 99% CSS, and the tree component is now using the FancyTree jQuery plugin rather than the dTree used in previous version of the TreeAndMenu extension. The new FancyTree has many options and plugins and is very extendable, please view the site and examples for more detail.

New features using FancyTree jQuery plugin

 * Can works natively with UL/LI structures which allows the PHP code to be much simpler
 * Supports Ajax loading of sub-nodes
 * Works in preview and diff pages, even live preview
 * Much more extendable and has many other extensions written for it
 * Actively developed code

Usage
Trees and menus are created by surrounding normal nested bullet list syntax with a parser-function as in the following examples.

The TreeAndMenu extension packages the tree with the ExtPersist plugin which allows the state of the tree to be maintained across page loads. To activate it use the following syntax:

The value of the extensions parameter is JSON so the quotes must be double not single. Other plugins can be added like this, but you'll need to load the JavaScript yourself.

Options can also be passed to the FancyTree code as well like this example (full list of available options here):

FancyTree options can also be passed to individual nodes with JSON syntax as follows, id and class values are put directly into the li element, all other JSON data is passed to the FancyTree code via a data-json attribute. Note that property names must also be quoted, not just values.

The following options are recognised: active, expanded, focus, folder, lazy, selected, unselectable

Styles
The style of trees is defined using CSS by adding the rules to your page. For example on my site I use the following to make the text and icons more like the last version of TreeAneMenu.

Dynamic Trees and Menus
You can use transclusion to embed the content of trees from other articles, or dynamically manipulate the content. For example a DPL query could generate the body of a treeview statement. Articles containing trees should not have any whitespace above the wikitex markup specifying the parser function tree otherwise the rendering can fail. Here's a dynamic example used in conjunction with Extension:ExtraMagic which creates a tree which exhibits some links that are only visible for sysops.


 * Note: The tree-view code will remove any empty items so they can work conditionally like this.

Here's another example of a dynamic tree using the DPL extension to make a tree which draws its items from all the articles in the foo category.

The query uses some DPL parameters to ensure that the results are preceded by double asterisks so that the items can appear inside the root node. See also this example for a more advanced use of DPL with tree-view to create a menu which contains two levels of outgoing links from a given page, or incoming pages to a given page.

Sub-trees
NOTE: This feature isn't working correctly in version 4.x, the transcluded content can only work with bullet lists and must use the correct depth as the dynamic queries are doing in the previous section.

Trees can be transcluded within other trees so we can define large trees from structures of smaller trees. Such sub-trees are defined using the following syntax:

In this example, an article called Tree2 is transcluded as an item in Tree1. Tree2 may be another tree or a normal bullet list, if it's a tree, then the attributes and options are ignored and the whole tree renders in accord with the attributes and options of the root tree.

Loading nodes with Ajax
The new FancyTree jQuery plugin has support for Ajax loading of nodes. This has been made accessible by the TreeAndMenu extension by passing an ajax option to FancyTree using the JSON syntax shown above. The value of the ajax option is the URL from which to retrieve the data containing the child nodes.

The URL is expected to contain either another tree, a plain bullet list, or JSON formatted array of nodes where each node is an object containing title, optional href key, and optional children array of sub-nodes. If the "ajax" option's value is not an absolute or relative URL, then it is assumed to be an article title and its content will be retrieved with action=render.

Adding a tree to the sidebar
One of the most common uses of this extension is to add a tree menu to the sidebar. This is easy if you're using your own custom skin, but if you want to do it without modifying the skin code, then you can use the following method.

As of MediaWiki 1.18 and later, I've found a good way to get wikitext into the sidebar is to attach a function to the BeforePageDisplay hook with the following content. Note that this example expects your tree to be defined in the MediaWiki:SidebarTree article. Note also that this code's id is independent of the id attribute you set for the tree itself, that (and the class attribute) are just for allowing different CSS for different trees.

This creates a div element (addressable with CSS by the "wikitext-sidebar" id attribute) containing the parsed content from the MediaWiki:SidebarTree article (it's best not to use the default MediaWiki:Sidebar article for this as it can cause some problems). You can then use some JavaScript added to your MediaWiki:Common.js to move the element into a more appropriate location in the page DOM. For example the following JavaScript snippet inserts the rendered wikitext below the site logo.

Opening a tree to the current page
The following example can be added to your MediaWiki:Common.js, it waits until the document is ready, then adds an event to a tree (selected by its id attribute, in this case #tree) so that when the tree is initialised it calls a helper function called makeTitleVisible which reveals and activates the first node linking to the current page.