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887 lines
23 KiB
JavaScript
887 lines
23 KiB
JavaScript
// TODO: remove unused: false
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/* jshint unused: false*/
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import Ember from 'ember';
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import ReusableListItemView from './reusable-list-item-view';
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var get = Ember.get;
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var set = Ember.set;
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var min = Math.min;
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var max = Math.max;
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var floor = Math.floor;
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var ceil = Math.ceil;
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var forEach = Ember.ArrayPolyfills.forEach;
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function addContentArrayObserver() {
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var content = get(this, 'content');
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if (content) {
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content.addArrayObserver(this);
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}
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}
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function removeAndDestroy(object) {
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this.removeObject(object);
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object.destroy();
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}
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function syncChildViews() {
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Ember.run.once(this, '_syncChildViews');
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}
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function sortByContentIndex (viewOne, viewTwo) {
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return get(viewOne, 'contentIndex') - get(viewTwo, 'contentIndex');
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}
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function removeEmptyView() {
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var emptyView = get(this, 'emptyView');
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if (emptyView && emptyView instanceof Ember.View) {
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emptyView.removeFromParent();
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if (this.totalHeightDidChange !== undefined) {
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this.totalHeightDidChange();
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}
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}
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}
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function addEmptyView() {
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var emptyView = get(this, 'emptyView');
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if (!emptyView) {
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return;
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}
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if ('string' === typeof emptyView) {
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emptyView = get(emptyView) || emptyView;
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}
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emptyView = this.createChildView(emptyView);
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set(this, 'emptyView', emptyView);
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if (Ember.CoreView.detect(emptyView)) {
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this._createdEmptyView = emptyView;
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}
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this.unshiftObject(emptyView);
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}
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function enableProfilingOutput() {
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function before(name, time/*, payload*/) {
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console.time(name);
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}
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function after (name, time/*, payload*/) {
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console.timeEnd(name);
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}
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if (Ember.ENABLE_PROFILING) {
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Ember.subscribe('view._scrollContentTo', {
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before: before,
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after: after
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});
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Ember.subscribe('view.updateContext', {
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before: before,
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after: after
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});
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}
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}
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/**
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@class Ember.ListViewMixin
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@namespace Ember
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*/
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export default Ember.Mixin.create({
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itemViewClass: ReusableListItemView,
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emptyViewClass: Ember.View,
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classNames: ['ember-list-view'],
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attributeBindings: ['style'],
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classNameBindings: ['_isGrid:ember-list-view-grid:ember-list-view-list'],
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scrollTop: 0,
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bottomPadding: 0, // TODO: maybe this can go away
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_lastEndingIndex: 0,
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paddingCount: 1,
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_cachedPos: 0,
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_isGrid: Ember.computed.gt('columnCount', 1).readOnly(),
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/**
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@private
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Setup a mixin.
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- adding observer to content array
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- creating child views based on height and length of the content array
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@method init
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*/
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init: function() {
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this._super();
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this._cachedHeights = [0];
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this.on('didInsertElement', this._syncListContainerWidth);
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this.columnCountDidChange();
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this._syncChildViews();
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this._addContentArrayObserver();
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},
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_addContentArrayObserver: Ember.beforeObserver(function() {
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addContentArrayObserver.call(this);
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}, 'content'),
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/**
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Called on your view when it should push strings of HTML into a
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`Ember.RenderBuffer`.
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Adds a [div](https://developer.mozilla.org/en-US/docs/HTML/Element/div)
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with a required `ember-list-container` class.
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@method render
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@param {Ember.RenderBuffer} buffer The render buffer
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*/
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render: function (buffer) {
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var element = buffer.element();
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var dom = buffer.dom;
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var container = dom.createElement('div');
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container.className = 'ember-list-container';
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element.appendChild(container);
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this._childViewsMorph = dom.appendMorph(container, container, null);
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return container;
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},
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createChildViewsMorph: function (element) {
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this._childViewsMorph = this._renderer._dom.createMorph(element.lastChild, element.lastChild, null);
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return element;
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},
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willInsertElement: function() {
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if (!this.get('height') || !this.get('rowHeight')) {
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throw new Error('A ListView must be created with a height and a rowHeight.');
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}
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this._super();
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},
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/**
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@private
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Sets inline styles of the view:
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- height
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- width
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- position
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- overflow
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- -webkit-overflow
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- overflow-scrolling
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Called while attributes binding.
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@property {Ember.ComputedProperty} style
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*/
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style: Ember.computed('height', 'width', function() {
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var height, width, style, css;
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height = get(this, 'height');
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width = get(this, 'width');
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css = get(this, 'css');
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style = '';
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if (height) {
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style += 'height:' + height + 'px;';
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}
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if (width) {
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style += 'width:' + width + 'px;';
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}
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for ( var rule in css ) {
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if (css.hasOwnProperty(rule)) {
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style += rule + ':' + css[rule] + ';';
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}
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}
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return Ember.String.htmlSafe(style);
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}),
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/**
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@private
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Performs visual scrolling. Is overridden in Ember.ListView.
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@method scrollTo
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*/
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scrollTo: function(y) {
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throw new Error('must override to perform the visual scroll and effectively delegate to _scrollContentTo');
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},
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/**
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@private
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Internal method used to force scroll position
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@method scrollTo
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*/
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_scrollTo: Ember.K,
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/**
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@private
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@method _scrollContentTo
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*/
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_scrollContentTo: function(y) {
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var startingIndex, endingIndex,
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contentIndex, visibleEndingIndex, maxContentIndex,
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contentIndexEnd, contentLength, scrollTop, content;
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scrollTop = max(0, y);
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if (this.scrollTop === scrollTop) {
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return;
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}
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// allow a visual overscroll, but don't scroll the content. As we are doing needless
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// recycyling, and adding unexpected nodes to the DOM.
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var maxScrollTop = max(0, get(this, 'totalHeight') - get(this, 'height'));
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scrollTop = min(scrollTop, maxScrollTop);
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content = get(this, 'content');
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contentLength = get(content, 'length');
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startingIndex = this._startingIndex(contentLength);
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Ember.instrument('view._scrollContentTo', {
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scrollTop: scrollTop,
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content: content,
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startingIndex: startingIndex,
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endingIndex: min(max(contentLength - 1, 0), startingIndex + this._numChildViewsForViewport())
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}, function () {
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this.scrollTop = scrollTop;
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maxContentIndex = max(contentLength - 1, 0);
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startingIndex = this._startingIndex();
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visibleEndingIndex = startingIndex + this._numChildViewsForViewport();
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endingIndex = min(maxContentIndex, visibleEndingIndex);
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if (startingIndex === this._lastStartingIndex &&
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endingIndex === this._lastEndingIndex) {
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this.trigger('scrollYChanged', y);
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return;
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} else {
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Ember.run(this, function() {
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this._reuseChildren();
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this._lastStartingIndex = startingIndex;
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this._lastEndingIndex = endingIndex;
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this.trigger('scrollYChanged', y);
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});
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}
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}, this);
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},
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/**
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@private
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Computes the height for a `Ember.ListView` scrollable container div.
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You must specify `rowHeight` parameter for the height to be computed properly.
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@property {Ember.ComputedProperty} totalHeight
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*/
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totalHeight: Ember.computed('content.length',
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'rowHeight',
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'columnCount',
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'bottomPadding', function() {
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if (typeof this.heightForIndex === 'function') {
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return this._totalHeightWithHeightForIndex();
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} else {
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return this._totalHeightWithStaticRowHeight();
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}
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}),
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_doRowHeightDidChange: function() {
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this._cachedHeights = [0];
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this._cachedPos = 0;
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this._syncChildViews();
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},
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_rowHeightDidChange: Ember.observer('rowHeight', function() {
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Ember.run.once(this, this._doRowHeightDidChange);
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}),
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_totalHeightWithHeightForIndex: function() {
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var length = this.get('content.length');
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return this._cachedHeightLookup(length);
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},
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_totalHeightWithStaticRowHeight: function() {
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var contentLength, rowHeight, columnCount, bottomPadding;
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contentLength = get(this, 'content.length');
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rowHeight = get(this, 'rowHeight');
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columnCount = get(this, 'columnCount');
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bottomPadding = get(this, 'bottomPadding');
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return ((ceil(contentLength / columnCount)) * rowHeight) + bottomPadding;
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},
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/**
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@private
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@method _prepareChildForReuse
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*/
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_prepareChildForReuse: function(childView) {
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childView.prepareForReuse();
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},
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createChildView: function (_view) {
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return this._super(_view, this._itemViewProps || {});
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},
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/**
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@private
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@method _reuseChildForContentIndex
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*/
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_reuseChildForContentIndex: function(childView, contentIndex) {
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var content, context, newContext, childsCurrentContentIndex, position, enableProfiling, oldChildView;
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var contentViewClass = this.itemViewForIndex(contentIndex);
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if (childView.constructor !== contentViewClass) {
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// rather then associative arrays, lets move childView + contentEntry maping to a Map
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var i = this._childViews.indexOf(childView);
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childView.destroy();
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childView = this.createChildView(contentViewClass);
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this.insertAt(i, childView);
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}
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content = get(this, 'content');
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enableProfiling = get(this, 'enableProfiling');
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position = this.positionForIndex(contentIndex);
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childView.updatePosition(position);
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set(childView, 'contentIndex', contentIndex);
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if (enableProfiling) {
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Ember.instrument('view._reuseChildForContentIndex', position, function() {
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}, this);
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}
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newContext = content.objectAt(contentIndex);
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childView.updateContext(newContext);
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},
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/**
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@private
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@method positionForIndex
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*/
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positionForIndex: function(index) {
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if (typeof this.heightForIndex !== 'function') {
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return this._singleHeightPosForIndex(index);
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}
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else {
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return this._multiHeightPosForIndex(index);
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}
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},
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_singleHeightPosForIndex: function(index) {
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var elementWidth, width, columnCount, rowHeight, y, x;
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elementWidth = get(this, 'elementWidth') || 1;
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width = get(this, 'width') || 1;
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columnCount = get(this, 'columnCount');
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rowHeight = get(this, 'rowHeight');
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y = (rowHeight * floor(index/columnCount));
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x = (index % columnCount) * elementWidth;
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return {
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y: y,
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x: x
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};
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},
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// 0 maps to 0, 1 maps to heightForIndex(i)
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_multiHeightPosForIndex: function(index) {
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var elementWidth, width, columnCount, rowHeight, y, x;
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elementWidth = get(this, 'elementWidth') || 1;
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width = get(this, 'width') || 1;
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columnCount = get(this, 'columnCount');
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x = (index % columnCount) * elementWidth;
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y = this._cachedHeightLookup(index);
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return {
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x: x,
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y: y
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};
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},
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_cachedHeightLookup: function(index) {
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for (var i = this._cachedPos; i < index; i++) {
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this._cachedHeights[i + 1] = this._cachedHeights[i] + this.heightForIndex(i);
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}
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this._cachedPos = i;
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return this._cachedHeights[index];
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},
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/**
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@private
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@method _childViewCount
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*/
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_childViewCount: function() {
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var contentLength, childViewCountForHeight;
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contentLength = get(this, 'content.length');
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childViewCountForHeight = this._numChildViewsForViewport();
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return min(contentLength, childViewCountForHeight);
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},
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/**
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@private
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Returns a number of columns in the Ember.ListView (for grid layout).
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If you want to have a multi column layout, you need to specify both
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`width` and `elementWidth`.
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If no `elementWidth` is specified, it returns `1`. Otherwise, it will
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try to fit as many columns as possible for a given `width`.
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@property {Ember.ComputedProperty} columnCount
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*/
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columnCount: Ember.computed('width', 'elementWidth', function() {
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var elementWidth, width, count;
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elementWidth = get(this, 'elementWidth');
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width = get(this, 'width');
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if (elementWidth && width > elementWidth) {
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count = floor(width / elementWidth);
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} else {
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count = 1;
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}
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return count;
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}),
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/**
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@private
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Fires every time column count is changed.
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@event columnCountDidChange
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*/
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columnCountDidChange: Ember.observer(function() {
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var ratio, currentScrollTop, proposedScrollTop, maxScrollTop,
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scrollTop, lastColumnCount, newColumnCount, element;
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lastColumnCount = this._lastColumnCount;
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currentScrollTop = this.scrollTop;
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newColumnCount = get(this, 'columnCount');
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maxScrollTop = get(this, 'maxScrollTop');
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element = this.element;
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this._lastColumnCount = newColumnCount;
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if (lastColumnCount) {
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ratio = (lastColumnCount / newColumnCount);
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proposedScrollTop = currentScrollTop * ratio;
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scrollTop = min(maxScrollTop, proposedScrollTop);
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this._scrollTo(scrollTop);
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this.scrollTop = scrollTop;
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}
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if (arguments.length > 0) {
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// invoked by observer
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Ember.run.schedule('afterRender', this, this._syncListContainerWidth);
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}
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}, 'columnCount'),
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/**
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@private
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Computes max possible scrollTop value given the visible viewport
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and scrollable container div height.
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@property {Ember.ComputedProperty} maxScrollTop
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*/
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maxScrollTop: Ember.computed('height', 'totalHeight', function(){
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var totalHeight, viewportHeight;
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totalHeight = get(this, 'totalHeight');
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viewportHeight = get(this, 'height');
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return max(0, totalHeight - viewportHeight);
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}),
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/**
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@private
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Determines whether the emptyView is the current childView.
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@method _isChildEmptyView
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*/
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_isChildEmptyView: function() {
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var emptyView = get(this, 'emptyView');
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return emptyView && emptyView instanceof Ember.View &&
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this._childViews.length === 1 && this._childViews.indexOf(emptyView) === 0;
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},
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/**
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@private
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Computes the number of views that would fit in the viewport area.
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You must specify `height` and `rowHeight` parameters for the number of
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views to be computed properly.
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@method _numChildViewsForViewport
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*/
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_numChildViewsForViewport: function() {
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if (this.heightForIndex) {
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return this._numChildViewsForViewportWithMultiHeight();
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} else {
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return this._numChildViewsForViewportWithoutMultiHeight();
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}
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},
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_numChildViewsForViewportWithoutMultiHeight: function() {
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var height, rowHeight, paddingCount, columnCount;
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height = get(this, 'height');
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rowHeight = get(this, 'rowHeight');
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paddingCount = get(this, 'paddingCount');
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columnCount = get(this, 'columnCount');
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return (ceil(height / rowHeight) * columnCount) + (paddingCount * columnCount);
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},
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_numChildViewsForViewportWithMultiHeight: function() {
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var rowHeight, paddingCount, columnCount;
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var scrollTop = this.scrollTop;
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var viewportHeight = this.get('height');
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var length = this.get('content.length');
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var heightfromTop = 0;
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var padding = get(this, 'paddingCount');
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var startingIndex = this._calculatedStartingIndex();
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var currentHeight = 0;
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var offsetHeight = this._cachedHeightLookup(startingIndex);
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for (var i = 0; i < length; i++) {
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if (this._cachedHeightLookup(startingIndex + i + 1) - offsetHeight > viewportHeight) {
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break;
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}
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}
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return i + padding + 1;
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},
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/**
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@private
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Computes the starting index of the item views array.
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Takes `scrollTop` property of the element into account.
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Is used in `_syncChildViews`.
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@method _startingIndex
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*/
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_startingIndex: function(_contentLength) {
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var scrollTop, rowHeight, columnCount, calculatedStartingIndex,
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contentLength;
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|
if (_contentLength === undefined) {
|
|
contentLength = get(this, 'content.length');
|
|
} else {
|
|
contentLength = _contentLength;
|
|
}
|
|
|
|
scrollTop = this.scrollTop;
|
|
rowHeight = get(this, 'rowHeight');
|
|
columnCount = get(this, 'columnCount');
|
|
|
|
if (this.heightForIndex) {
|
|
calculatedStartingIndex = this._calculatedStartingIndex();
|
|
} else {
|
|
calculatedStartingIndex = floor(scrollTop / rowHeight) * columnCount;
|
|
}
|
|
|
|
var viewsNeededForViewport = this._numChildViewsForViewport();
|
|
var paddingCount = (1 * columnCount);
|
|
var largestStartingIndex = max(contentLength - viewsNeededForViewport, 0);
|
|
|
|
return min(calculatedStartingIndex, largestStartingIndex);
|
|
},
|
|
|
|
_calculatedStartingIndex: function() {
|
|
var rowHeight, paddingCount, columnCount;
|
|
var scrollTop = this.scrollTop;
|
|
var viewportHeight = this.get('height');
|
|
var length = this.get('content.length');
|
|
var heightfromTop = 0;
|
|
var padding = get(this, 'paddingCount');
|
|
|
|
for (var i = 0; i < length; i++) {
|
|
if (this._cachedHeightLookup(i + 1) >= scrollTop) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
return i;
|
|
},
|
|
|
|
/**
|
|
@private
|
|
@event contentWillChange
|
|
*/
|
|
contentWillChange: Ember.beforeObserver(function() {
|
|
var content = get(this, 'content');
|
|
|
|
if (content) {
|
|
content.removeArrayObserver(this);
|
|
}
|
|
}, 'content'),
|
|
|
|
/**),
|
|
@private
|
|
@event contentDidChange
|
|
*/
|
|
contentDidChange: Ember.observer(function() {
|
|
addContentArrayObserver.call(this);
|
|
syncChildViews.call(this);
|
|
}, 'content'),
|
|
|
|
/**
|
|
@private
|
|
@property {Function} needsSyncChildViews
|
|
*/
|
|
needsSyncChildViews: Ember.observer(syncChildViews, 'height', 'width', 'columnCount'),
|
|
|
|
/**
|
|
@private
|
|
|
|
Returns a new item view. Takes `contentIndex` to set the context
|
|
of the returned view properly.
|
|
|
|
@param {Number} contentIndex item index in the content array
|
|
@method _addItemView
|
|
*/
|
|
_addItemView: function (contentIndex) {
|
|
var itemViewClass, childView;
|
|
|
|
itemViewClass = this.itemViewForIndex(contentIndex);
|
|
childView = this.createChildView(itemViewClass);
|
|
this.pushObject(childView);
|
|
},
|
|
|
|
/**
|
|
@public
|
|
|
|
Returns a view class for the provided contentIndex. If the view is
|
|
different then the one currently present it will remove the existing view
|
|
and replace it with an instance of the class provided
|
|
|
|
@param {Number} contentIndex item index in the content array
|
|
@method _addItemView
|
|
@returns {Ember.View} ember view class for this index
|
|
*/
|
|
itemViewForIndex: function(contentIndex) {
|
|
return get(this, 'itemViewClass');
|
|
},
|
|
|
|
/**
|
|
@public
|
|
|
|
Returns a view class for the provided contentIndex. If the view is
|
|
different then the one currently present it will remove the existing view
|
|
and replace it with an instance of the class provided
|
|
|
|
@param {Number} contentIndex item index in the content array
|
|
@method _addItemView
|
|
@returns {Ember.View} ember view class for this index
|
|
*/
|
|
heightForIndex: null,
|
|
|
|
/**
|
|
@private
|
|
|
|
Intelligently manages the number of childviews.
|
|
|
|
@method _syncChildViews
|
|
**/
|
|
_syncChildViews: function () {
|
|
var childViews, childViewCount,
|
|
numberOfChildViews, numberOfChildViewsNeeded,
|
|
contentIndex, startingIndex, endingIndex,
|
|
contentLength, emptyView, count, delta;
|
|
|
|
if (this.isDestroyed || this.isDestroying) {
|
|
return;
|
|
}
|
|
|
|
contentLength = get(this, 'content.length');
|
|
emptyView = get(this, 'emptyView');
|
|
|
|
childViewCount = this._childViewCount();
|
|
childViews = this.positionOrderedChildViews();
|
|
|
|
if (this._isChildEmptyView()) {
|
|
removeEmptyView.call(this);
|
|
}
|
|
|
|
startingIndex = this._startingIndex();
|
|
endingIndex = startingIndex + childViewCount;
|
|
|
|
numberOfChildViewsNeeded = childViewCount;
|
|
numberOfChildViews = childViews.length;
|
|
|
|
delta = numberOfChildViewsNeeded - numberOfChildViews;
|
|
|
|
if (delta === 0) {
|
|
// no change
|
|
} else if (delta > 0) {
|
|
// more views are needed
|
|
contentIndex = this._lastEndingIndex;
|
|
|
|
for (count = 0; count < delta; count++, contentIndex++) {
|
|
this._addItemView(contentIndex);
|
|
}
|
|
} else {
|
|
// less views are needed
|
|
forEach.call(
|
|
childViews.splice(numberOfChildViewsNeeded, numberOfChildViews),
|
|
removeAndDestroy,
|
|
this
|
|
);
|
|
}
|
|
|
|
this._reuseChildren();
|
|
|
|
this._lastStartingIndex = startingIndex;
|
|
this._lastEndingIndex = this._lastEndingIndex + delta;
|
|
|
|
if (contentLength === 0 || contentLength === undefined) {
|
|
addEmptyView.call(this);
|
|
}
|
|
},
|
|
|
|
/**
|
|
@private
|
|
|
|
Applies an inline width style to the list container.
|
|
|
|
@method _syncListContainerWidth
|
|
**/
|
|
_syncListContainerWidth: function() {
|
|
var elementWidth, columnCount, containerWidth, element;
|
|
|
|
elementWidth = get(this, 'elementWidth');
|
|
columnCount = get(this, 'columnCount');
|
|
containerWidth = elementWidth * columnCount;
|
|
element = this.$('.ember-list-container');
|
|
|
|
if (containerWidth && element) {
|
|
element.css('width', containerWidth);
|
|
}
|
|
},
|
|
|
|
/**
|
|
@private
|
|
@method _reuseChildren
|
|
*/
|
|
_reuseChildren: function(){
|
|
var contentLength, childViews, childViewsLength,
|
|
startingIndex, endingIndex, childView, attrs,
|
|
contentIndex, visibleEndingIndex, maxContentIndex,
|
|
contentIndexEnd, scrollTop;
|
|
|
|
scrollTop = this.scrollTop;
|
|
contentLength = get(this, 'content.length');
|
|
maxContentIndex = max(contentLength - 1, 0);
|
|
childViews = this.getReusableChildViews();
|
|
childViewsLength = childViews.length;
|
|
|
|
startingIndex = this._startingIndex();
|
|
visibleEndingIndex = startingIndex + this._numChildViewsForViewport();
|
|
|
|
endingIndex = min(maxContentIndex, visibleEndingIndex);
|
|
|
|
contentIndexEnd = min(visibleEndingIndex, startingIndex + childViewsLength);
|
|
|
|
for (contentIndex = startingIndex; contentIndex < contentIndexEnd; contentIndex++) {
|
|
childView = childViews[contentIndex % childViewsLength];
|
|
this._reuseChildForContentIndex(childView, contentIndex);
|
|
}
|
|
},
|
|
|
|
/**
|
|
@private
|
|
@method getReusableChildViews
|
|
*/
|
|
getReusableChildViews: function() {
|
|
return this._childViews;
|
|
},
|
|
|
|
/**
|
|
@private
|
|
@method positionOrderedChildViews
|
|
*/
|
|
positionOrderedChildViews: function() {
|
|
return this.getReusableChildViews().sort(sortByContentIndex);
|
|
},
|
|
|
|
arrayWillChange: Ember.K,
|
|
|
|
/**
|
|
@private
|
|
@event arrayDidChange
|
|
*/
|
|
// TODO: refactor
|
|
arrayDidChange: function(content, start, removedCount, addedCount) {
|
|
var index, contentIndex, state;
|
|
|
|
if (this._isChildEmptyView()) {
|
|
removeEmptyView.call(this);
|
|
}
|
|
|
|
// Support old and new Ember versions
|
|
state = this._state || this.state;
|
|
|
|
if (state === 'inDOM') {
|
|
// ignore if all changes are out of the visible change
|
|
if (start >= this._lastStartingIndex || start < this._lastEndingIndex) {
|
|
index = 0;
|
|
// ignore all changes not in the visible range
|
|
// this can re-position many, rather then causing a cascade of re-renders
|
|
forEach.call(
|
|
this.positionOrderedChildViews(),
|
|
function(childView) {
|
|
contentIndex = this._lastStartingIndex + index;
|
|
this._reuseChildForContentIndex(childView, contentIndex);
|
|
index++;
|
|
},
|
|
this
|
|
);
|
|
}
|
|
|
|
syncChildViews.call(this);
|
|
}
|
|
},
|
|
|
|
destroy: function () {
|
|
if (!this._super()) {
|
|
return;
|
|
}
|
|
|
|
if (this._createdEmptyView) {
|
|
this._createdEmptyView.destroy();
|
|
}
|
|
|
|
return this;
|
|
}
|
|
});
|