const { calculateIndex } = Utils; BlazeComponent.extendComponent({ // Proxy openForm(options) { this.childComponents('listBody')[0].openForm(options); }, onCreated() { this.newCardFormIsVisible = new ReactiveVar(true); }, // The jquery UI sortable library is the best solution I've found so far. I // tried sortable and dragula but they were not powerful enough four our use // case. I also considered writing/forking a drag-and-drop + sortable library // but it's probably too much work. // By calling asking the sortable library to cancel its move on the `stop` // callback, we basically solve all issues related to reactive updates. A // comment below provides further details. onRendered() { const boardComponent = this.parentComponent(); const itemsSelector = '.js-minicard:not(.placeholder, .js-card-composer)'; const $cards = this.$('.js-minicards'); $cards.sortable({ connectWith: '.js-minicards', tolerance: 'pointer', appendTo: 'body', helper(evt, item) { const helper = item.clone(); if (MultiSelection.isActive()) { const andNOthers = $cards.find('.js-minicard.is-checked').length - 1; if (andNOthers > 0) { helper.append($(Blaze.toHTML(HTML.DIV( { 'class': 'and-n-other' }, TAPi18n.__('and-n-other-card', { count: andNOthers }) )))); } } return helper; }, distance: 7, items: itemsSelector, scroll: false, placeholder: 'minicard-wrapper placeholder', start(evt, ui) { ui.placeholder.height(ui.helper.height()); EscapeActions.executeUpTo('popup-close'); boardComponent.setIsDragging(true); }, stop(evt, ui) { // To attribute the new index number, we need to get the DOM element // of the previous and the following card -- if any. const prevCardDom = ui.item.prev('.js-minicard').get(0); const nextCardDom = ui.item.next('.js-minicard').get(0); const nCards = MultiSelection.isActive() ? MultiSelection.count() : 1; const sortIndex = calculateIndex(prevCardDom, nextCardDom, nCards); const listId = Blaze.getData(ui.item.parents('.list').get(0))._id; // Normally the jquery-ui sortable library moves the dragged DOM element // to its new position, which disrupts Blaze reactive updates mechanism // (especially when we move the last card of a list, or when multiple // users move some cards at the same time). To prevent these UX glitches // we ask sortable to gracefully cancel the move, and to put back the // DOM in its initial state. The card move is then handled reactively by // Blaze with the below query. $cards.sortable('cancel'); if (MultiSelection.isActive()) { Cards.find(MultiSelection.getMongoSelector()).forEach((card, i) => { card.move(listId, sortIndex.base + i * sortIndex.increment); }); } else { const cardDomElement = ui.item.get(0); const card = Blaze.getData(cardDomElement); card.move(listId, sortIndex.base); } boardComponent.setIsDragging(false); }, }); function userIsMember() { return Meteor.user() && Meteor.user().isBoardMember() && !Meteor.user().isCommentOnly(); } // Disable drag-dropping if the current user is not a board member or is comment only this.autorun(() => { $cards.sortable('option', 'disabled', !userIsMember()); }); // We want to re-run this function any time a card is added. this.autorun(() => { const currentBoardId = Tracker.nonreactive(() => { return Session.get('currentBoard'); }); Cards.find({ boardId: currentBoardId }).fetch(); Tracker.afterFlush(() => { $cards.find(itemsSelector).droppable({ hoverClass: 'draggable-hover-card', accept: '.js-member,.js-label', drop(event, ui) { const cardId = Blaze.getData(this)._id; const card = Cards.findOne(cardId); if (ui.draggable.hasClass('js-member')) { const memberId = Blaze.getData(ui.draggable.get(0)).userId; card.assignMember(memberId); } else { const labelId = Blaze.getData(ui.draggable.get(0))._id; card.addLabel(labelId); } }, }); }); }); }, }).register('list');