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action is not described

customize_preview_(type) action-hook . WP 4.1.0

Fires when the WP_Customize_Setting::preview() method is called for settings not handled as theme_mods or options.

The dynamic portion of the hook name, $this->type, refers to the setting type.

Usage

add_action( 'customize_preview_(type)', 'action_function_name_7002' );
function action_function_name_7002( $this ){
	// action...
}
$this(WP_Customize_Setting)
WP_Customize_Setting instance.

Where the hook is called

WP_Customize_Setting::preview()
wp-includes/class-wp-customize-setting.php 398
do_action( "customize_preview_{$this->type}", $this );

Where the hook is used (in WP core)

wp-includes/customize/class-wp-customize-selective-refresh.php 67
add_action( 'customize_preview_init', array( $this, 'init_preview' ) );
wp-includes/class-wp-customize-widgets.php 119
add_action( 'customize_preview_init', array( $this, 'customize_preview_init' ) );
wp-includes/class-wp-customize-widgets.php 128
add_action( 'customize_preview_init', array( $this, 'selective_refresh_init' ) );
wp-includes/class-wp-customize-nav-menus.php 66
add_action( 'customize_preview_init', array( $this, 'customize_preview_init' ) );
wp-includes/class-wp-customize-nav-menus.php 67
add_action( 'customize_preview_init', array( $this, 'make_auto_draft_status_previewable' ) );