Posted by InternetDevels on October 7, 2015 at 2:15pm
In Drupal 7 API there is a chapter dedicated to site theming. From a Drupal developer's point of view, almost everything is done with the help of functions and there are many of them that facilitate theming in Drupal 7, too.
The most important one is the theme() function.
In the blog post by our developer, 2 of them are analyzed:
1) theme_table() – function for table formatting.
2) theme_fieldset() – function for drop-down list.
http://internetdevels.com/blog/examples-themetable-and-themefieldset-functions-drupal-7