after_switch_theme action-hookWP 3.3.0

Fires on the first WP load after a theme switch if the old theme still exists.

This action fires multiple times and the parameters differs according to the context, if the old theme exists or not. If the old theme is missing, the parameter will be the slug of the old theme.


add_action( 'after_switch_theme', 'wp_kama_after_switch_theme_action', 10, 2 );

 * Function for `after_switch_theme` action-hook.
 * @param string   $old_name  Old theme name.
 * @param WP_Theme $old_theme WP_Theme instance of the old theme.
 * @return void
function wp_kama_after_switch_theme_action( $old_name, $old_theme ){

	// action...
Old theme name.
WP_Theme instance of the old theme.


Since 3.3.0 Introduced.

Where the hook is called

wp-includes/theme.php 3377
do_action( 'after_switch_theme', $old_theme->get( 'Name' ), $old_theme );
wp-includes/theme.php 3380
do_action( 'after_switch_theme', $stylesheet, $old_theme );

Where the hook is used in WordPress

wp-includes/default-filters.php 350
add_action( 'after_switch_theme', '_wp_menus_changed' );
wp-includes/default-filters.php 351
add_action( 'after_switch_theme', '_wp_sidebars_changed' );
wp-includes/theme.php 3358
remove_action( 'after_switch_theme', '_wp_menus_changed' );
wp-includes/theme.php 3359
remove_action( 'after_switch_theme', '_wp_sidebars_changed' );