Theming basics

This section contains reference material useful for understanding Elgg's theming system.

Elgg's default theme

In the previous chapters, you have seen many screenshots of Elgg's default theme. It is not a plugin that can be removed, but is built into Elgg. Theming is the process of replacing elements of the default theme. In this section, we provide an overview of the four main components of the theme: HTML, CSS, JavaScript, and graphics.

HTML

Elgg uses semantic HTML (sometimes called Plain Old Semantic HTML or POSH). With semantic HTML, the markup describes the meaning of the content rather than the presentation of it. The following are a few characteristics of semantic HTML:

• Tables are used to describe tabular data, not for layouts

• Menus tend to be lists of links so a list element is used

• Paragraph tags are used to mark paragraphs, not for spacing purposes

• Semantic CSS classes (using a class of error instead of red)

A primary advantage of this approach is that it is more intuitive...