ThemeLayer

Big picture: Drupal Core Default Theme  =>   Real Theme

Definitions:

  • HOOK:  A placehoder that must be replaced by, 'node', 'page', ect, or by a user theme name or user module name.
  • $vars:  An array of variables and arrays.  $vars[title] == $vars['title'] will turn into $title when it is handed to the template file or theme function (not sure how).
  • Template file: Mix of HTML & PHP and produces HTML output  shown on web page. HOOKname.tpl.php. The core template HOOKnames are: html, page, block, node, field, etc etc.
  • Theme function: Equivalent to a template file but for programmers instead of designers. Generates HTML output. Core theme functions are named theme_HOOK($vars), theme_breadcrumb(), etc. . API
  • theme($hook, $var): THE theme function (not one of the template-file equivalents). E.g. if $hook='node' it will call either the node template file or the node theme function and pass it $var from which it will generate HTML. API
  • Override: A template file of the same name in sites/all/themes/ will be run instead of the core template file. page--article.tpl.php will override core page.tpl.php for article nodes.
  •  

Three Scenarios:

  1. Build something (e.g. myblock) and theme it with a theme function in a module
  2. Build something and theme it with a template
  3. Tamper with the default or real theme

Scenario #1: Theme function. Define:   function theme_myblock($vars) { ... }

  • $vars = array( items => array('cat' => $cat; 'dog' => $dog,), 'title' => $title, type => $type, attributes => $attribs);
  • Never call function  theme_myblocks($vars).  Instead call:
  • theme('myblocks', $vars);
  • And drupal will call your function at the right time.

 


Info about head_title http://drupal.org/node/655742