#APEX_CSS# placeholder is substituted in the
head tag of the Page Template.
As you can see from the screenshot it’s really straight forward to load a file.
#MIN_DIRECTORY# substitution too. I think those substitutions are especially important for optimizing the size of files loaded by a Plug-in. Please see online help for details.
As a summary, in 95% of your Plug-ins you shouldn’t have to use
apex_css.add_file ( p_name => 'jquery.rating', p_directory => p_plugin.file_prefix );
in you PL/SQL code anymore.
BTW, what’s also not yet documented in the online help is that you can also use
#JQUERYUI_DIRECTORY# to reference the latest jQueryUI version used by APEX. For example if you want to include the Slider widget which is not automatically loaded by APEX you can use
to always pick up the most current jQueryUI version.