Widgets: Introduce Gallery widget for displaying image galleries.

* Galleries are managed in the widget in the same way they are managed in the post editor, both using the media manager.
* Gallery widget is merged from the Core Media Widgets v0.2.0 feature plugin and it extends `WP_Widget_Media` in the same way as is done for image, audio, and video widgets.
* Model syncing logic is updated to support booleans and arrays (of integers).
* Placeholder areas in media widgets are now clickable shortcuts for selecting media.
* Image widget placeholder is updated to match gallery widget where clicking preview is shortcut for editing media.

Props westonruter, joemcgill, timmydcrawford, m1tk00, obenland, melchoyce.
See #32417.
Fixes #41914.


git-svn-id: https://develop.svn.wordpress.org/trunk@41590 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/css/widgets.css

@@ -87,7 +87,7 @@
 .media-widget-control .placeholder {
 	border: 1px dashed #b4b9be;
 	box-sizing: border-box;
-	cursor: default;
+	cursor: pointer;
 	line-height: 20px;
 	padding: 9px 0;
 	position: relative;
@@ -162,6 +162,71 @@
 	margin: 1em 0;
 }
 
+.media-widget-gallery-preview {
+	display: -webkit-box;
+	display: flex;
+	-webkit-box-pack: start;
+	justify-content: flex-start;
+	flex-wrap: wrap;
+}
+
+.media-widget-preview.media_gallery,
+.media-widget-preview.media_image {
+	cursor: pointer;
+}
+
+.media-widget-gallery-preview .gallery-item {
+	box-sizing: border-box;
+	width: 50%;
+	margin: 0;
+	padding: 1.79104477%;
+}
+
+/*
+ * Use targeted nth-last-child selectors to control the size of each image
+ * based on how many gallery items are present in the grid.
+ * See: https://alistapart.com/article/quantity-queries-for-css
+ */
+.media-widget-gallery-preview .gallery-item:nth-last-child(3):first-child,
+.media-widget-gallery-preview .gallery-item:nth-last-child(3):first-child ~ .gallery-item,
+.media-widget-gallery-preview .gallery-item:nth-last-child(n+5),
+.media-widget-gallery-preview .gallery-item:nth-last-child(n+5) ~ .gallery-item,
+.media-widget-gallery-preview .gallery-item:nth-last-child(n+6),
+.media-widget-gallery-preview .gallery-item:nth-last-child(n+6) ~ .gallery-item {
+	max-width: 33.33%;
+}
+
+.media-widget-gallery-preview .gallery-item img {
+	height: auto;
+	vertical-align: bottom;
+}
+
+.media-widget-gallery-preview .gallery-icon {
+	position: relative;
+}
+
+.media-widget-gallery-preview .gallery-icon-placeholder {
+	position: absolute;
+	top: 0;
+	bottom: 0;
+	width: 100%;
+	box-sizing: border-box;
+	display: -webkit-box;
+	display: flex;
+	-webkit-box-align: center;
+	align-items: center;
+	-webkit-box-pack: center;
+	justify-content: center;
+	background-color: rgba( 0, 0, 0, .5 );
+}
+
+.media-widget-gallery-preview .gallery-icon-placeholder-text {
+	font-weight: 600;
+	font-size: 2em;
+	color: white;
+}
+
+
 /* Widget Dragging Helpers */
 .widget.ui-draggable-dragging {
 	min-width: 100%;

src/wp-admin/js/widgets/media-gallery-widget.js

@@ -0,0 +1,325 @@
+/* eslint consistent-this: [ "error", "control" ] */
+(function( component ) {
+	'use strict';
+
+	var GalleryWidgetModel, GalleryWidgetControl, GalleryDetailsMediaFrame;
+
+	/**
+	 * Custom gallery details frame.
+	 *
+	 * @since 4.9.0
+	 * @class GalleryDetailsMediaFrame
+	 * @constructor
+	 */
+	GalleryDetailsMediaFrame = wp.media.view.MediaFrame.Post.extend( {
+
+		/**
+		 * Create the default states.
+		 *
+		 * @since 4.9.0
+		 * @returns {void}
+		 */
+		createStates: function createStates() {
+			this.states.add([
+				new wp.media.controller.Library({
+					id:         'gallery',
+					title:      wp.media.view.l10n.createGalleryTitle,
+					priority:   40,
+					toolbar:    'main-gallery',
+					filterable: 'uploaded',
+					multiple:   'add',
+					editable:   true,
+
+					library:  wp.media.query( _.defaults({
+						type: 'image'
+					}, this.options.library ) )
+				}),
+
+				// Gallery states.
+				new wp.media.controller.GalleryEdit({
+					library: this.options.selection,
+					editing: this.options.editing,
+					menu:    'gallery'
+				}),
+
+				new wp.media.controller.GalleryAdd()
+			]);
+		}
+	} );
+
+	/**
+	 * Gallery widget model.
+	 *
+	 * See WP_Widget_Gallery::enqueue_admin_scripts() for amending prototype from PHP exports.
+	 *
+	 * @since 4.9.0
+	 * @class GalleryWidgetModel
+	 * @constructor
+	 */
+	GalleryWidgetModel = component.MediaWidgetModel.extend( {} );
+
+	/**
+	 * Gallery widget control.
+	 *
+	 * See WP_Widget_Gallery::enqueue_admin_scripts() for amending prototype from PHP exports.
+	 *
+	 * @since 4.9.0
+	 * @class GalleryWidgetControl
+	 * @constructor
+	 */
+	GalleryWidgetControl = component.MediaWidgetControl.extend( {
+
+		/**
+		 * View events.
+		 *
+		 * @since 4.9.0
+		 * @type {object}
+		 */
+		events: _.extend( {}, component.MediaWidgetControl.prototype.events, {
+			'click .media-widget-gallery-preview': 'editMedia'
+		} ),
+
+		/**
+		 * Initialize.
+		 *
+		 * @since 4.9.0
+		 * @param {Object}         options - Options.
+		 * @param {Backbone.Model} options.model - Model.
+		 * @param {jQuery}         options.el - Control field container element.
+		 * @param {jQuery}         options.syncContainer - Container element where fields are synced for the server.
+		 * @returns {void}
+		 */
+		initialize: function initialize( options ) {
+			var control = this;
+
+			component.MediaWidgetControl.prototype.initialize.call( control, options );
+
+			_.bindAll( control, 'updateSelectedAttachments', 'handleAttachmentDestroy' );
+			control.selectedAttachments = new wp.media.model.Attachments();
+			control.model.on( 'change:ids', control.updateSelectedAttachments );
+			control.selectedAttachments.on( 'change', control.renderPreview );
+			control.selectedAttachments.on( 'reset', control.renderPreview );
+			control.updateSelectedAttachments();
+		},
+
+		/**
+		 * Update the selected attachments if necessary.
+		 *
+		 * @since 4.9.0
+		 * @returns {void}
+		 */
+		updateSelectedAttachments: function updateSelectedAttachments() {
+			var control = this, newIds, oldIds, removedIds, addedIds, addedQuery;
+
+			newIds = control.model.get( 'ids' );
+			oldIds = _.pluck( control.selectedAttachments.models, 'id' );
+
+			removedIds = _.difference( oldIds, newIds );
+			_.each( removedIds, function( removedId ) {
+				control.selectedAttachments.remove( control.selectedAttachments.get( removedId ) );
+			});
+
+			addedIds = _.difference( newIds, oldIds );
+			if ( addedIds.length ) {
+				addedQuery = wp.media.query({
+					order: 'ASC',
+					orderby: 'post__in',
+					perPage: -1,
+					post__in: newIds,
+					query: true,
+					type: 'image'
+				});
+				addedQuery.more().done( function() {
+					control.selectedAttachments.reset( addedQuery.models );
+				});
+			}
+		},
+
+		/**
+		 * Render preview.
+		 *
+		 * @since 4.9.0
+		 * @returns {void}
+		 */
+		renderPreview: function renderPreview() {
+			var control = this, previewContainer, previewTemplate, data;
+
+			previewContainer = control.$el.find( '.media-widget-preview' );
+			previewTemplate = wp.template( 'wp-media-widget-gallery-preview' );
+
+			data = control.previewTemplateProps.toJSON();
+			data.attachments = {};
+			control.selectedAttachments.each( function( attachment ) {
+				data.attachments[ attachment.id ] = attachment.toJSON();
+			} );
+
+			previewContainer.html( previewTemplate( data ) );
+		},
+
+		/**
+		 * Determine whether there are selected attachments.
+		 *
+		 * @since 4.9.0
+		 * @returns {boolean} Selected.
+		 */
+		isSelected: function isSelected() {
+			var control = this;
+
+			if ( control.model.get( 'error' ) ) {
+				return false;
+			}
+
+			return control.model.get( 'ids' ).length > 0;
+		},
+
+		/**
+		 * Open the media select frame to edit images.
+		 *
+		 * @since 4.9.0
+		 * @returns {void}
+		 */
+		editMedia: function editMedia() {
+			var control = this, selection, mediaFrame, mediaFrameProps;
+
+			selection = new wp.media.model.Selection( control.selectedAttachments.models, {
+				multiple: true
+			});
+
+			mediaFrameProps = control.mapModelToMediaFrameProps( control.model.toJSON() );
+			selection.gallery = new Backbone.Model( _.pick( mediaFrameProps, 'columns', 'link', 'size', '_orderbyRandom' ) );
+			if ( mediaFrameProps.size ) {
+				control.displaySettings.set( 'size', mediaFrameProps.size );
+			}
+			mediaFrame = new GalleryDetailsMediaFrame({
+				frame: 'manage',
+				text: control.l10n.add_to_widget,
+				selection: selection,
+				mimeType: control.mime_type,
+				selectedDisplaySettings: control.displaySettings,
+				showDisplaySettings: control.showDisplaySettings,
+				metadata: mediaFrameProps,
+				editing:   true,
+				multiple:  true,
+				state: 'gallery-edit'
+			});
+			wp.media.frame = mediaFrame; // See wp.media().
+
+			// Handle selection of a media item.
+			mediaFrame.on( 'update', function onUpdate( newSelection ) {
+				var state = mediaFrame.state(), resultSelection;
+
+				resultSelection = newSelection || state.get( 'selection' );
+				if ( ! resultSelection ) {
+					return;
+				}
+
+				// Copy orderby_random from gallery state.
+				if ( resultSelection.gallery ) {
+					control.model.set( control.mapMediaToModelProps( resultSelection.gallery.toJSON() ) );
+				}
+
+				// Directly update selectedAttachments to prevent needing to do additional request.
+				control.selectedAttachments.reset( resultSelection.models );
+
+				// Update models in the widget instance.
+				control.model.set( {
+					ids: _.pluck( resultSelection.models, 'id' )
+				} );
+			} );
+
+			mediaFrame.$el.addClass( 'media-widget' );
+			mediaFrame.open();
+
+			if ( selection ) {
+				selection.on( 'destroy', control.handleAttachmentDestroy );
+			}
+		},
+
+		/**
+		 * Open the media select frame to chose an item.
+		 *
+		 * @since 4.9.0
+		 * @returns {void}
+		 */
+		selectMedia: function selectMedia() {
+			var control = this, selection, mediaFrame, mediaFrameProps;
+			selection = new wp.media.model.Selection( control.selectedAttachments.models, {
+				multiple: true
+			});
+
+			mediaFrameProps = control.mapModelToMediaFrameProps( control.model.toJSON() );
+			if ( mediaFrameProps.size ) {
+				control.displaySettings.set( 'size', mediaFrameProps.size );
+			}
+			mediaFrame = new GalleryDetailsMediaFrame({
+				frame: 'select',
+				text: control.l10n.add_to_widget,
+				selection: selection,
+				mimeType: control.mime_type,
+				selectedDisplaySettings: control.displaySettings,
+				showDisplaySettings: control.showDisplaySettings,
+				metadata: mediaFrameProps,
+				state: 'gallery'
+			});
+			wp.media.frame = mediaFrame; // See wp.media().
+
+			// Handle selection of a media item.
+			mediaFrame.on( 'update', function onUpdate( newSelection ) {
+				var state = mediaFrame.state(), resultSelection;
+
+				resultSelection = newSelection || state.get( 'selection' );
+				if ( ! resultSelection ) {
+					return;
+				}
+
+				// Copy orderby_random from gallery state.
+				if ( resultSelection.gallery ) {
+					control.model.set( control.mapMediaToModelProps( resultSelection.gallery.toJSON() ) );
+				}
+
+				// Directly update selectedAttachments to prevent needing to do additional request.
+				control.selectedAttachments.reset( resultSelection.models );
+
+				// Update widget instance.
+				control.model.set( {
+					ids: _.pluck( resultSelection.models, 'id' )
+				} );
+			} );
+
+			mediaFrame.$el.addClass( 'media-widget' );
+			mediaFrame.open();
+
+			if ( selection ) {
+				selection.on( 'destroy', control.handleAttachmentDestroy );
+			}
+
+			/*
+			 * Make sure focus is set inside of modal so that hitting Esc will close
+			 * the modal and not inadvertently cause the widget to collapse in the customizer.
+			 */
+			mediaFrame.$el.find( ':focusable:first' ).focus();
+		},
+
+		/**
+		 * Clear the selected attachment when it is deleted in the media select frame.
+		 *
+		 * @since 4.9.0
+		 * @param {wp.media.models.Attachment} attachment - Attachment.
+		 * @returns {void}
+		 */
+		handleAttachmentDestroy: function handleAttachmentDestroy( attachment ) {
+			var control = this;
+			control.model.set( {
+				ids: _.difference(
+					control.model.get( 'ids' ),
+					[ attachment.id ]
+				)
+			} );
+		}
+	} );
+
+	// Exports.
+	component.controlConstructors.media_gallery = GalleryWidgetControl;
+	component.modelConstructors.media_gallery = GalleryWidgetModel;
+
+})( wp.mediaWidgets );

src/wp-admin/js/widgets/media-image-widget.js

@@ -24,6 +24,15 @@
 	 */
 	ImageWidgetControl = component.MediaWidgetControl.extend({
 
+		/**
+		 * View events.
+		 *
+		 * @type {object}
+		 */
+		events: _.extend( {}, component.MediaWidgetControl.prototype.events, {
+			'click .media-widget-preview.populated': 'editMedia'
+		} ),
+
 		/**
 		 * Render preview.
 		 *
@@ -38,6 +47,7 @@
 			previewContainer = control.$el.find( '.media-widget-preview' );
 			previewTemplate = wp.template( 'wp-media-widget-image-preview' );
 			previewContainer.html( previewTemplate( control.previewTemplateProps.toJSON() ) );
+			previewContainer.addClass( 'populated' );
 
 			linkInput = control.$el.find( '.link' );
 			if ( ! linkInput.is( document.activeElement ) ) {

src/wp-admin/js/widgets/media-widgets.js

@@ -429,6 +429,7 @@ wp.mediaWidgets = ( function( $ ) {
 		events: {
 			'click .notice-missing-attachment a': 'handleMediaLibraryLinkClick',
 			'click .select-media': 'selectMedia',
+			'click .placeholder': 'selectMedia',
 			'click .edit-media': 'editMedia'
 		},
 
@@ -591,17 +592,25 @@ wp.mediaWidgets = ( function( $ ) {
 		syncModelToInputs: function syncModelToInputs() {
 			var control = this;
 			control.syncContainer.find( '.media-widget-instance-property' ).each( function() {
-				var input = $( this ), value;
-				value = control.model.get( input.data( 'property' ) );
+				var input = $( this ), value, propertyName;
+				propertyName = input.data( 'property' );
+				value = control.model.get( propertyName );
 				if ( _.isUndefined( value ) ) {
 					return;
 				}
-				value = String( value );
-				if ( input.val() === value ) {
-					return;
+
+				if ( 'array' === control.model.schema[ propertyName ].type && _.isArray( value ) ) {
+					value = value.join( ',' );
+				} else if ( 'boolean' === control.model.schema[ propertyName ].type ) {
+					value = value ? '1' : ''; // Because in PHP, strval( true ) === '1' && strval( false ) === ''.
+				} else {
+					value = String( value );
+				}
+
+				if ( input.val() !== value ) {
+					input.val( value );
+					input.trigger( 'change' );
 				}
-				input.val( value );
-				input.trigger( 'change' );
 			});
 		},
 
@@ -1002,7 +1011,22 @@ wp.mediaWidgets = ( function( $ ) {
 					return;
 				}
 				type = model.schema[ name ].type;
-				if ( 'integer' === type ) {
+				if ( 'array' === type ) {
+					castedAttrs[ name ] = value;
+					if ( ! _.isArray( castedAttrs[ name ] ) ) {
+						castedAttrs[ name ] = castedAttrs[ name ].split( /,/ ); // Good enough for parsing an ID list.
+					}
+					if ( model.schema[ name ].items && 'integer' === model.schema[ name ].items.type ) {
+						castedAttrs[ name ] = _.filter(
+							_.map( castedAttrs[ name ], function( id ) {
+								return parseInt( id, 10 );
+							},
+							function( id ) {
+								return 'number' === typeof id;
+							}
+						) );
+					}
+				} else if ( 'integer' === type ) {
 					castedAttrs[ name ] = parseInt( value, 10 );
 				} else if ( 'boolean' === type ) {
 					castedAttrs[ name ] = ! ( ! value || '0' === value || 'false' === value );