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Diffstat (limited to 'vendor/oojs/oojs-ui/src/elements/DraggableGroupElement.js')
-rw-r--r-- | vendor/oojs/oojs-ui/src/elements/DraggableGroupElement.js | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/vendor/oojs/oojs-ui/src/elements/DraggableGroupElement.js b/vendor/oojs/oojs-ui/src/elements/DraggableGroupElement.js new file mode 100644 index 00000000..134e2953 --- /dev/null +++ b/vendor/oojs/oojs-ui/src/elements/DraggableGroupElement.js @@ -0,0 +1,261 @@ +/** + * DraggableGroupElement is a mixin class used to create a group element to + * contain draggable elements, which are items that can be clicked and dragged by a mouse. + * The class is used with OO.ui.DraggableElement. + * + * @abstract + * @class + * @mixins OO.ui.GroupElement + * + * @constructor + * @param {Object} [config] Configuration options + * @cfg {string} [orientation] Item orientation: 'horizontal' or 'vertical'. The orientation + * should match the layout of the items. Items displayed in a single row + * or in several rows should use horizontal orientation. The vertical orientation should only be + * used when the items are displayed in a single column. Defaults to 'vertical' + */ +OO.ui.DraggableGroupElement = function OoUiDraggableGroupElement( config ) { + // Configuration initialization + config = config || {}; + + // Parent constructor + OO.ui.GroupElement.call( this, config ); + + // Properties + this.orientation = config.orientation || 'vertical'; + this.dragItem = null; + this.itemDragOver = null; + this.itemKeys = {}; + this.sideInsertion = ''; + + // Events + this.aggregate( { + dragstart: 'itemDragStart', + dragend: 'itemDragEnd', + drop: 'itemDrop' + } ); + this.connect( this, { + itemDragStart: 'onItemDragStart', + itemDrop: 'onItemDrop', + itemDragEnd: 'onItemDragEnd' + } ); + this.$element.on( { + dragover: $.proxy( this.onDragOver, this ), + dragleave: $.proxy( this.onDragLeave, this ) + } ); + + // Initialize + if ( Array.isArray( config.items ) ) { + this.addItems( config.items ); + } + this.$placeholder = $( '<div>' ) + .addClass( 'oo-ui-draggableGroupElement-placeholder' ); + this.$element + .addClass( 'oo-ui-draggableGroupElement' ) + .append( this.$status ) + .toggleClass( 'oo-ui-draggableGroupElement-horizontal', this.orientation === 'horizontal' ) + .prepend( this.$placeholder ); +}; + +/* Setup */ +OO.mixinClass( OO.ui.DraggableGroupElement, OO.ui.GroupElement ); + +/* Events */ + +/** + * A 'reorder' event is emitted when the order of items in the group changes. + * + * @event reorder + * @param {OO.ui.DraggableElement} item Reordered item + * @param {number} [newIndex] New index for the item + */ + +/* Methods */ + +/** + * Respond to item drag start event + * + * @private + * @param {OO.ui.DraggableElement} item Dragged item + */ +OO.ui.DraggableGroupElement.prototype.onItemDragStart = function ( item ) { + var i, len; + + // Map the index of each object + for ( i = 0, len = this.items.length; i < len; i++ ) { + this.items[ i ].setIndex( i ); + } + + if ( this.orientation === 'horizontal' ) { + // Set the height of the indicator + this.$placeholder.css( { + height: item.$element.outerHeight(), + width: 2 + } ); + } else { + // Set the width of the indicator + this.$placeholder.css( { + height: 2, + width: item.$element.outerWidth() + } ); + } + this.setDragItem( item ); +}; + +/** + * Respond to item drag end event + * + * @private + */ +OO.ui.DraggableGroupElement.prototype.onItemDragEnd = function () { + this.unsetDragItem(); + return false; +}; + +/** + * Handle drop event and switch the order of the items accordingly + * + * @private + * @param {OO.ui.DraggableElement} item Dropped item + * @fires reorder + */ +OO.ui.DraggableGroupElement.prototype.onItemDrop = function ( item ) { + var toIndex = item.getIndex(); + // Check if the dropped item is from the current group + // TODO: Figure out a way to configure a list of legally droppable + // elements even if they are not yet in the list + if ( this.getDragItem() ) { + // If the insertion point is 'after', the insertion index + // is shifted to the right (or to the left in RTL, hence 'after') + if ( this.sideInsertion === 'after' ) { + toIndex++; + } + // Emit change event + this.emit( 'reorder', this.getDragItem(), toIndex ); + } + this.unsetDragItem(); + // Return false to prevent propogation + return false; +}; + +/** + * Handle dragleave event. + * + * @private + */ +OO.ui.DraggableGroupElement.prototype.onDragLeave = function () { + // This means the item was dragged outside the widget + this.$placeholder + .css( 'left', 0 ) + .addClass( 'oo-ui-element-hidden' ); +}; + +/** + * Respond to dragover event + * + * @private + * @param {jQuery.Event} event Event details + */ +OO.ui.DraggableGroupElement.prototype.onDragOver = function ( e ) { + var dragOverObj, $optionWidget, itemOffset, itemMidpoint, itemBoundingRect, + itemSize, cssOutput, dragPosition, itemIndex, itemPosition, + clientX = e.originalEvent.clientX, + clientY = e.originalEvent.clientY; + + // Get the OptionWidget item we are dragging over + dragOverObj = this.getElementDocument().elementFromPoint( clientX, clientY ); + $optionWidget = $( dragOverObj ).closest( '.oo-ui-draggableElement' ); + if ( $optionWidget[ 0 ] ) { + itemOffset = $optionWidget.offset(); + itemBoundingRect = $optionWidget[ 0 ].getBoundingClientRect(); + itemPosition = $optionWidget.position(); + itemIndex = $optionWidget.data( 'index' ); + } + + if ( + itemOffset && + this.isDragging() && + itemIndex !== this.getDragItem().getIndex() + ) { + if ( this.orientation === 'horizontal' ) { + // Calculate where the mouse is relative to the item width + itemSize = itemBoundingRect.width; + itemMidpoint = itemBoundingRect.left + itemSize / 2; + dragPosition = clientX; + // Which side of the item we hover over will dictate + // where the placeholder will appear, on the left or + // on the right + cssOutput = { + left: dragPosition < itemMidpoint ? itemPosition.left : itemPosition.left + itemSize, + top: itemPosition.top + }; + } else { + // Calculate where the mouse is relative to the item height + itemSize = itemBoundingRect.height; + itemMidpoint = itemBoundingRect.top + itemSize / 2; + dragPosition = clientY; + // Which side of the item we hover over will dictate + // where the placeholder will appear, on the top or + // on the bottom + cssOutput = { + top: dragPosition < itemMidpoint ? itemPosition.top : itemPosition.top + itemSize, + left: itemPosition.left + }; + } + // Store whether we are before or after an item to rearrange + // For horizontal layout, we need to account for RTL, as this is flipped + if ( this.orientation === 'horizontal' && this.$element.css( 'direction' ) === 'rtl' ) { + this.sideInsertion = dragPosition < itemMidpoint ? 'after' : 'before'; + } else { + this.sideInsertion = dragPosition < itemMidpoint ? 'before' : 'after'; + } + // Add drop indicator between objects + this.$placeholder + .css( cssOutput ) + .removeClass( 'oo-ui-element-hidden' ); + } else { + // This means the item was dragged outside the widget + this.$placeholder + .css( 'left', 0 ) + .addClass( 'oo-ui-element-hidden' ); + } + // Prevent default + e.preventDefault(); +}; + +/** + * Set a dragged item + * + * @param {OO.ui.DraggableElement} item Dragged item + */ +OO.ui.DraggableGroupElement.prototype.setDragItem = function ( item ) { + this.dragItem = item; +}; + +/** + * Unset the current dragged item + */ +OO.ui.DraggableGroupElement.prototype.unsetDragItem = function () { + this.dragItem = null; + this.itemDragOver = null; + this.$placeholder.addClass( 'oo-ui-element-hidden' ); + this.sideInsertion = ''; +}; + +/** + * Get the item that is currently being dragged. + * + * @return {OO.ui.DraggableElement|null} The currently dragged item, or `null` if no item is being dragged + */ +OO.ui.DraggableGroupElement.prototype.getDragItem = function () { + return this.dragItem; +}; + +/** + * Check if an item in the group is currently being dragged. + * + * @return {Boolean} Item is being dragged + */ +OO.ui.DraggableGroupElement.prototype.isDragging = function () { + return this.getDragItem() !== null; +}; |