Recipe 76: Understanding how Theme functions are called

As our theme_pager function demonstrates, it is not unusual to find themeable functions calling other themeable functions. Being able to detect these building blocks is a good step toward deeper Drupal understanding.

Themeable functions are called by modules and themes using the theme() function. Some examples will be helpful:

General Example

theme_function_name is called using the following syntax:

theme('function_name', parameter, parameter…)

Specific Example #1

1. Visit http://api.freestylesystems.co.uk/api/function/theme_views_view/5

   This is an excerpt of the views.module, containing the theme_views_view function. Each time a view is built this function is run.

2. Locate the spot in the code where the theme_view_more function is called.

   theme('views_more', $view->real_url);

   (In the full code, the function result is assigned to the $output variable.)

   Make note of the surrounding "if statement" controlling the theme_views_more output.

       if ...