app/ directory contains all of the theme functionality. Since Sage is a starter theme, it’s okay for you to modify files within
app/ to meet the needs of the site you’re building.
The PHP code in Sage is namespaced, so make sure to use namespaced functions and classes.
app/setup.php– Enqueue stylesheets and scripts, register support for theme features with
add_theme_support, register navigation menus and sidebars. See Theme Configuration and Setup.
app/admin.php– Placeholder code for the WordPress theme customizer. You can also use this file for anything related to the WordPress admin.
app/filters.php– Add WordPress filters in this file. Filters included by default:
excerpt_more– add "… Continued" to excerpts
template_include– enable the theme wrapper
- Various filters for the Blade implementation
app/helpers.php– Helper functions used throughout the theme:
asset_path– used when enqueueing theme assets to provide the correct versioned asset filenames
display_sidebar– used to control displaying the sidebar
title– used to return page titles