get_default_button_labels example

    public function __construct( $manager, $id, $args = array() ) {
        parent::__construct( $manager, $id, $args );

        $this->button_labels = wp_parse_args( $this->button_labels, $this->get_default_button_labels() );
    }

    /** * Enqueue control related scripts/styles. * * @since 3.4.0 * @since 4.2.0 Moved from WP_Customize_Upload_Control. */
    public function enqueue() {
        wp_enqueue_media();
    }