The register_theme_directory() WordPress PHP function registers a directory that contains themes.
Usage
register_theme_directory($directory);
Example:
Input:
register_theme_directory('/path/to/your/theme/directory');
Parameters
$directory(string) – The full filesystem path to a theme folder or a folder withinWP_CONTENT_DIR.
More information
See WordPress Developer Resources: register_theme_directory()
Examples
Registering a plugin’s subdirectory as a theme folder
Explanation: The following code registers a subdirectory within a plugin as a theme folder. This is useful if you want to include custom themes with your plugin.
// Register a plugin's subdirectory as a theme folder register_theme_directory(dirname(__FILE__) . '/themes');
Registering a custom theme folder outside of the default wp-content/themes folder
Explanation: The following code registers a custom theme folder that is located outside the default wp-content/themes folder.
// Register a custom theme folder
register_theme_directory('/path/to/your/custom/theme/folder');
Registering a theme folder inside a custom wp-content folder
Explanation: If you have a custom wp-content folder, you can use this code to register a theme folder within that custom folder.
// Register a theme folder inside a custom wp-content folder register_theme_directory(WP_CONTENT_DIR . '/your-theme-folder');
Registering a theme folder inside a child theme
Explanation: The following code registers a theme folder inside a child theme. This is useful if you want to include additional themes with your child theme.
// Register a theme folder inside a child theme register_theme_directory(get_stylesheet_directory() . '/additional-themes');
Registering a theme folder inside a mu-plugin
Explanation: If you want to include themes with a must-use plugin (mu-plugin), you can use this code to register a theme folder inside the mu-plugin.
// Register a theme folder inside a mu-plugin register_theme_directory(WPMU_PLUGIN_DIR . '/your-mu-plugin/themes');