Drupal 6 Theming for Module Developers - Suggesting TPLs From a Module. A common problem that Drupal module developers run into is: creating a module with an appealing default user-interface, but also allowing designers to easily override the default UI, in a theme.
There are multiple ways to solve this problem. While Drupal theme architecture is certainly capable of allowing such implementations, the exact code you need to write depends on which kind of template you are providing default implementation for. Whether you are “suggesting” a views template, node template or custom template you may need to write code in different ways. In all use-cases described below, you can create a tpl.php in your module and designers can customize it simply by copying the file to a default theme and editing it. Style Guide. Provides a visual testing page for Drupal themes.
Quickly compare the display of common elements across your themes, and verify that your new theme addresses all common style elements. The Style Guide module creates a preview page for displaying common theme elements in all active themes for your Drupal site. The module comes with previews for common HTML elements, such as tables, forms, links and lists. Demo site. Development Seed.