WP_Customize_Header_Image_Setting

19final class WP_Customize_Header_Image_Setting extends WP_Customize_Setting {20 21	/**22	 * Unique string identifier for the setting.23	 *24	 * @since 3.4.025	 * @var string26	 */27	public $id = 'header_image_data';28 29	/**30	 * @since 3.4.031	 * @since 7.0.0 Return type updated from void to true for compatibility with base class.32	 *33	 * @global Custom_Image_Header $custom_image_header34	 *35	 * @param mixed $value The value to update.36	 * @return true Always returns true.37	 */38	public function update( $value ) {39		global $custom_image_header;40 41		// If _custom_header_background_just_in_time() fails to initialize $custom_image_header when not is_admin().42		if ( empty( $custom_image_header ) ) {43			require_once ABSPATH . 'wp-admin/includes/class-custom-image-header.php';44			$args                   = get_theme_support( 'custom-header' );45			$admin_head_callback    = $args[0]['admin-head-callback'] ?? null;46			$admin_preview_callback = $args[0]['admin-preview-callback'] ?? null;47			$custom_image_header    = new Custom_Image_Header( $admin_head_callback, $admin_preview_callback );48		}49 50		/*51		 * If the value doesn't exist (removed or random),52		 * use the header_image value.53		 */54		if ( ! $value ) {55			$value = $this->manager->get_setting( 'header_image' )->post_value();56		}57 58		if ( is_array( $value ) && isset( $value['choice'] ) ) {59			$custom_image_header->set_header_image( $value['choice'] );60		} else {61			$custom_image_header->set_header_image( $value );62		}63		return true;64	}65}