next_tag( 'img' ) || null === $processor->get_attribute( 'src' ) ) { return ''; } if ( isset( $attributes['data-id'] ) ) { // Add the data-id="$id" attribute to the img element // to provide backwards compatibility for the Gallery Block, // which now wraps Image Blocks within innerBlocks. // The data-id attribute is added in a core/gallery `render_block_data` hook. $processor->set_attribute( 'data-id', $attributes['data-id'] ); } $link_destination = isset( $attributes['linkDestination'] ) ? $attributes['linkDestination'] : 'none'; $lightbox_settings = block_core_image_get_lightbox_settings( $block->parsed_block ); /* * If the lightbox is enabled and the image is not linked, add the filter * and the JavaScript view file. */ if ( isset( $lightbox_settings ) && 'none' === $link_destination && isset( $lightbox_settings['enabled'] ) && true === $lightbox_settings['enabled'] ) { wp_enqueue_script_module( '@wordpress/block-library/image' ); /* * This render needs to happen in a filter with priority 15 to ensure that * it runs after the duotone filter and that duotone styles are applied to * the image in the lightbox. Lightbox has to work with any plugins that * might use filters as well. Removing this can be considered in the * future if the way the blocks are rendered changes, or if a * new kind of filter is introduced. */ add_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15, 2 ); } else { /* * Remove the filter if previously added by other Image blocks. */ remove_filter( 'render_block_core/image', 'block_core_image_render_lightbox', 15 ); } return $processor->get_updated_html(); } /** * Adds the lightboxEnabled flag to the block data. * * This is used to determine whether the lightbox should be rendered or not. * * @param array $block Block data. * * @return array Filtered block data. */ function block_core_image_get_lightbox_settings( $block ) { // Get the lightbox setting from the block attributes. if ( isset( $block['attrs']['lightbox'] ) ) { $lightbox_settings = $block['attrs']['lightbox']; } if ( ! isset( $lightbox_settings ) ) { $lightbox_settings = wp_get_global_settings( array( 'lightbox' ), array( 'block_name' => 'core/image' ) ); // If not present in global settings, check the top-level global settings. // // NOTE: If no block-level settings are found, the previous call to // `wp_get_global_settings` will return the whole `theme.json` // structure in which case we can check if the "lightbox" key is present at // the top-level of the global settings and use its value. if ( isset( $lightbox_settings['lightbox'] ) ) { $lightbox_settings = wp_get_global_settings( array( 'lightbox' ) ); } } return $lightbox_settings ?? null; } /** * Adds the directives and layout needed for the lightbox behavior. * * @param string $block_content Rendered block content. * @param array $block Block object. * * @return string Filtered block content. */ function block_core_image_render_lightbox( $block_content, $block ) { /* * If it's not possible that an IMG element exists then return the given * block content as-is. It may be that there's no actual image in the block * or it could be that another plugin already modified this HTML. */ if ( false === stripos( $block_content, 'next_tag( 'img' ) ) { return $block_content; } $alt_attribute = $processor->get_attribute( 'alt' ); // An empty alt attribute `alt=""` is valid for decorative images. if ( is_string( $alt_attribute ) ) { $alt_attribute = trim( $alt_attribute ); } // It only makes sense to append the alt text to the button aria-label when the alt text is non-empty. if ( $alt_attribute ) { /* translators: %s: Image alt text. */ $aria_label = sprintf( __( 'Enlarge image: %s' ), $alt_attribute ); } // Currently, we are only enabling the zoom animation. $lightbox_animation = 'zoom'; // Note: We want to store the `src` in the context so we // can set it dynamically when the lightbox is opened. if ( isset( $block['attrs']['id'] ) ) { $img_uploaded_src = wp_get_attachment_url( $block['attrs']['id'] ); $img_metadata = wp_get_attachment_metadata( $block['attrs']['id'] ); $img_width = $img_metadata['width'] ?? 'none'; $img_height = $img_metadata['height'] ?? 'none'; } else { $img_uploaded_src = $processor->get_attribute( 'src' ); $img_width = 'none'; $img_height = 'none'; } if ( isset( $block['attrs']['scale'] ) ) { $scale_attr = $block['attrs']['scale']; } else { $scale_attr = false; } $w = new WP_HTML_Tag_Processor( $block_content ); $w->next_tag( 'figure' ); $w->add_class( 'wp-lightbox-container' ); $w->set_attribute( 'data-wp-interactive', '{"namespace":"core/image"}' ); $w->set_attribute( 'data-wp-context', sprintf( '{ "imageLoaded": false, "initialized": false, "lightboxEnabled": false, "hideAnimationEnabled": false, "preloadInitialized": false, "lightboxAnimation": "%s", "imageUploadedSrc": "%s", "imageCurrentSrc": "", "targetWidth": "%s", "targetHeight": "%s", "scaleAttr": "%s", "dialogLabel": "%s" }', $lightbox_animation, $img_uploaded_src, $img_width, $img_height, $scale_attr, __( 'Enlarged image' ) ) ); $w->next_tag( 'img' ); $w->set_attribute( 'data-wp-init', 'callbacks.initOriginImage' ); $w->set_attribute( 'data-wp-on--load', 'actions.handleLoad' ); $w->set_attribute( 'data-wp-watch', 'callbacks.setButtonStyles' ); // We need to set an event callback on the `img` specifically // because the `figure` element can also contain a caption, and // we don't want to trigger the lightbox when the caption is clicked. $w->set_attribute( 'data-wp-on--click', 'actions.showLightbox' ); $w->set_attribute( 'data-wp-watch--setStylesOnResize', 'callbacks.setStylesOnResize' ); $body_content = $w->get_updated_html(); // Add a button alongside image in the body content. $img = null; preg_match( '/]+>/', $body_content, $img ); $button = $img[0] . ''; $body_content = preg_replace( '/]+>/', $button, $body_content ); // We need both a responsive image and an enlarged image to animate // the zoom seamlessly on slow internet connections; the responsive // image is a copy of the one in the body, which animates immediately // as the lightbox is opened, while the enlarged one is a full-sized // version that will likely still be loading as the animation begins. $m = new WP_HTML_Tag_Processor( $block_content ); $m->next_tag( 'figure' ); $m->add_class( 'responsive-image' ); $m->next_tag( 'img' ); // We want to set the 'src' attribute to an empty string in the responsive image // because otherwise, as of this writing, the wp_filter_content_tags() function in // WordPress will automatically add a 'srcset' attribute to the image, which will at // times cause the incorrectly sized image to be loaded in the lightbox on Firefox. // Because of this, we bind the 'src' attribute explicitly the current src to reliably // use the exact same image as in the content when the lightbox is first opened while // we wait for the larger image to load. $m->set_attribute( 'src', '' ); $m->set_attribute( 'data-wp-bind--src', 'context.imageCurrentSrc' ); $m->set_attribute( 'data-wp-style--object-fit', 'state.lightboxObjectFit' ); $initial_image_content = $m->get_updated_html(); $q = new WP_HTML_Tag_Processor( $block_content ); $q->next_tag( 'figure' ); $q->add_class( 'enlarged-image' ); $q->next_tag( 'img' ); // We set the 'src' attribute to an empty string to prevent the browser from loading the image // on initial page load, then bind the attribute to a selector that returns the full-sized image src when // the lightbox is opened. We could use 'loading=lazy' in combination with the 'hidden' attribute to // accomplish the same behavior, but that approach breaks progressive loading of the image in Safari // and Chrome (see https://github.com/WordPress/gutenberg/pull/52765#issuecomment-1674008151). Until that // is resolved, manually setting the 'src' seems to be the best solution to load the large image on demand. $q->set_attribute( 'src', '' ); $q->set_attribute( 'data-wp-bind--src', 'state.enlargedImgSrc' ); $q->set_attribute( 'data-wp-style--object-fit', 'state.lightboxObjectFit' ); $enlarged_image_content = $q->get_updated_html(); // If the current theme does NOT have a `theme.json`, or the colors are not defined, // we need to set the background color & close button color to some default values // because we can't get them from the Global Styles. $background_color = '#fff'; $close_button_color = '#000'; if ( wp_theme_has_theme_json() ) { $global_styles_color = wp_get_global_styles( array( 'color' ) ); if ( ! empty( $global_styles_color['background'] ) ) { $background_color = esc_attr( $global_styles_color['background'] ); } if ( ! empty( $global_styles_color['text'] ) ) { $close_button_color = esc_attr( $global_styles_color['text'] ); } } $close_button_icon = ''; $close_button_label = esc_attr__( 'Close' ); $lightbox_html = << HTML; return str_replace( '', $lightbox_html . '', $body_content ); } /** * Registers the `core/image` block on server. */ function register_block_core_image() { register_block_type_from_metadata( __DIR__ . '/image', array( 'render_callback' => 'render_block_core_image', ) ); wp_register_script_module( '@wordpress/block-library/image', defined( 'IS_GUTENBERG_PLUGIN' ) && IS_GUTENBERG_PLUGIN ? gutenberg_url( '/build/interactivity/image.min.js' ) : includes_url( 'blocks/image/view.min.js' ), array( '@wordpress/interactivity' ), defined( 'GUTENBERG_VERSION' ) ? GUTENBERG_VERSION : get_bloginfo( 'version' ) ); } add_action( 'init', 'register_block_core_image' );