vis.js is a dynamic, browser-based visualization library
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/**
* Create a timeline visualization
* @param {HTMLElement} container
* @param {vis.DataSet | Array | google.visualization.DataTable} [items]
* @param {Object} [options] See Timeline.setOptions for the available options.
* @constructor
*/
function Timeline (container, items, options) {
if (!(this instanceof Timeline)) {
throw new SyntaxError('Constructor must be called with the new operator');
}
var me = this;
this.defaultOptions = {
start: null,
end: null,
autoResize: true,
orientation: 'bottom',
width: null,
height: null,
maxHeight: null,
minHeight: null
};
this.options = util.deepExtend({}, this.defaultOptions);
// Create the DOM, props, and emitter
this._create(container);
// all components listed here will be repainted automatically
this.components = [];
this.body = {
dom: this.dom,
domProps: this.props,
emitter: {
on: this.on.bind(this),
off: this.off.bind(this),
emit: this.emit.bind(this)
},
util: {
snap: null, // will be specified after TimeAxis is created
toScreen: me._toScreen.bind(me),
toGlobalScreen: me._toGlobalScreen.bind(me), // this refers to the root.width
toTime: me._toTime.bind(me),
toGlobalTime : me._toGlobalTime.bind(me)
}
};
// range
this.range = new Range(this.body);
this.components.push(this.range);
this.body.range = this.range;
// time axis
this.timeAxis = new TimeAxis(this.body);
this.components.push(this.timeAxis);
this.body.util.snap = this.timeAxis.snap.bind(this.timeAxis);
// current time bar
this.currentTime = new CurrentTime(this.body);
this.components.push(this.currentTime);
// custom time bar
// Note: time bar will be attached in this.setOptions when selected
this.customTime = new CustomTime(this.body);
this.components.push(this.customTime);
// item set
this.itemSet = new ItemSet(this.body);
this.components.push(this.itemSet);
this.itemsData = null; // DataSet
this.groupsData = null; // DataSet
// apply options
if (options) {
this.setOptions(options);
}
// create itemset
if (items) {
this.setItems(items);
}
else {
this.redraw();
}
}
// turn Timeline into an event emitter
Emitter(Timeline.prototype);
/**
* Create the main DOM for the Timeline: a root panel containing left, right,
* top, bottom, content, and background panel.
* @param {Element} container The container element where the Timeline will
* be attached.
* @private
*/
Timeline.prototype._create = function (container) {
this.dom = {};
this.dom.root = document.createElement('div');
this.dom.background = document.createElement('div');
this.dom.backgroundVertical = document.createElement('div');
this.dom.backgroundHorizontal = document.createElement('div');
this.dom.centerContainer = document.createElement('div');
this.dom.leftContainer = document.createElement('div');
this.dom.rightContainer = document.createElement('div');
this.dom.center = document.createElement('div');
this.dom.left = document.createElement('div');
this.dom.right = document.createElement('div');
this.dom.top = document.createElement('div');
this.dom.bottom = document.createElement('div');
this.dom.shadowTop = document.createElement('div');
this.dom.shadowBottom = document.createElement('div');
this.dom.shadowTopLeft = document.createElement('div');
this.dom.shadowBottomLeft = document.createElement('div');
this.dom.shadowTopRight = document.createElement('div');
this.dom.shadowBottomRight = document.createElement('div');
this.dom.background.className = 'vispanel background';
this.dom.backgroundVertical.className = 'vispanel background vertical';
this.dom.backgroundHorizontal.className = 'vispanel background horizontal';
this.dom.centerContainer.className = 'vispanel center';
this.dom.leftContainer.className = 'vispanel left';
this.dom.rightContainer.className = 'vispanel right';
this.dom.top.className = 'vispanel top';
this.dom.bottom.className = 'vispanel bottom';
this.dom.left.className = 'content';
this.dom.center.className = 'content';
this.dom.right.className = 'content';
this.dom.shadowTop.className = 'shadow top';
this.dom.shadowBottom.className = 'shadow bottom';
this.dom.shadowTopLeft.className = 'shadow top';
this.dom.shadowBottomLeft.className = 'shadow bottom';
this.dom.shadowTopRight.className = 'shadow top';
this.dom.shadowBottomRight.className = 'shadow bottom';
this.dom.root.appendChild(this.dom.background);
this.dom.root.appendChild(this.dom.backgroundVertical);
this.dom.root.appendChild(this.dom.backgroundHorizontal);
this.dom.root.appendChild(this.dom.centerContainer);
this.dom.root.appendChild(this.dom.leftContainer);
this.dom.root.appendChild(this.dom.rightContainer);
this.dom.root.appendChild(this.dom.top);
this.dom.root.appendChild(this.dom.bottom);
this.dom.centerContainer.appendChild(this.dom.center);
this.dom.leftContainer.appendChild(this.dom.left);
this.dom.rightContainer.appendChild(this.dom.right);
this.dom.centerContainer.appendChild(this.dom.shadowTop);
this.dom.centerContainer.appendChild(this.dom.shadowBottom);
this.dom.leftContainer.appendChild(this.dom.shadowTopLeft);
this.dom.leftContainer.appendChild(this.dom.shadowBottomLeft);
this.dom.rightContainer.appendChild(this.dom.shadowTopRight);
this.dom.rightContainer.appendChild(this.dom.shadowBottomRight);
this.on('rangechange', this.redraw.bind(this));
this.on('change', this.redraw.bind(this));
this.on('touch', this._onTouch.bind(this));
this.on('pinch', this._onPinch.bind(this));
this.on('dragstart', this._onDragStart.bind(this));
this.on('drag', this._onDrag.bind(this));
// create event listeners for all interesting events, these events will be
// emitted via emitter
this.hammer = Hammer(this.dom.root, {
prevent_default: true
});
this.listeners = {};
var me = this;
var events = [
'touch', 'pinch',
'tap', 'doubletap', 'hold',
'dragstart', 'drag', 'dragend',
'mousewheel', 'DOMMouseScroll' // DOMMouseScroll is needed for Firefox
];
events.forEach(function (event) {
var listener = function () {
var args = [event].concat(Array.prototype.slice.call(arguments, 0));
me.emit.apply(me, args);
};
me.hammer.on(event, listener);
me.listeners[event] = listener;
});
// size properties of each of the panels
this.props = {
root: {},
background: {},
centerContainer: {},
leftContainer: {},
rightContainer: {},
center: {},
left: {},
right: {},
top: {},
bottom: {},
border: {},
scrollTop: 0,
scrollTopMin: 0
};
this.touch = {}; // store state information needed for touch events
// attach the root panel to the provided container
if (!container) throw new Error('No container provided');
container.appendChild(this.dom.root);
};
/**
* Destroy the Timeline, clean up all DOM elements and event listeners.
*/
Timeline.prototype.destroy = function () {
// unbind datasets
this.clear();
// remove all event listeners
this.off();
// stop checking for changed size
this._stopAutoResize();
// remove from DOM
if (this.dom.root.parentNode) {
this.dom.root.parentNode.removeChild(this.dom.root);
}
this.dom = null;
// cleanup hammer touch events
for (var event in this.listeners) {
if (this.listeners.hasOwnProperty(event)) {
delete this.listeners[event];
}
}
this.listeners = null;
this.hammer = null;
// give all components the opportunity to cleanup
this.components.forEach(function (component) {
component.destroy();
});
this.body = null;
};
/**
* Set options. Options will be passed to all components loaded in the Timeline.
* @param {Object} [options]
* {String} orientation
* Vertical orientation for the Timeline,
* can be 'bottom' (default) or 'top'.
* {String | Number} width
* Width for the timeline, a number in pixels or
* a css string like '1000px' or '75%'. '100%' by default.
* {String | Number} height
* Fixed height for the Timeline, a number in pixels or
* a css string like '400px' or '75%'. If undefined,
* The Timeline will automatically size such that
* its contents fit.
* {String | Number} minHeight
* Minimum height for the Timeline, a number in pixels or
* a css string like '400px' or '75%'.
* {String | Number} maxHeight
* Maximum height for the Timeline, a number in pixels or
* a css string like '400px' or '75%'.
* {Number | Date | String} start
* Start date for the visible window
* {Number | Date | String} end
* End date for the visible window
*/
Timeline.prototype.setOptions = function (options) {
if (options) {
// copy the known options
var fields = ['width', 'height', 'minHeight', 'maxHeight', 'autoResize', 'start', 'end', 'orientation'];
util.selectiveExtend(fields, this.options, options);
// enable/disable autoResize
this._initAutoResize();
}
// propagate options to all components
this.components.forEach(function (component) {
component.setOptions(options);
});
// TODO: remove deprecation error one day (deprecated since version 0.8.0)
if (options && options.order) {
throw new Error('Option order is deprecated. There is no replacement for this feature.');
}
// redraw everything
this.redraw();
};
/**
* Set a custom time bar
* @param {Date} time
*/
Timeline.prototype.setCustomTime = function (time) {
if (!this.customTime) {
throw new Error('Cannot get custom time: Custom time bar is not enabled');
}
this.customTime.setCustomTime(time);
};
/**
* Retrieve the current custom time.
* @return {Date} customTime
*/
Timeline.prototype.getCustomTime = function() {
if (!this.customTime) {
throw new Error('Cannot get custom time: Custom time bar is not enabled');
}
return this.customTime.getCustomTime();
};
/**
* Set items
* @param {vis.DataSet | Array | google.visualization.DataTable | null} items
*/
Timeline.prototype.setItems = function(items) {
var initialLoad = (this.itemsData == null);
// convert to type DataSet when needed
var newDataSet;
if (!items) {
newDataSet = null;
}
else if (items instanceof DataSet || items instanceof DataView) {
newDataSet = items;
}
else {
// turn an array into a dataset
newDataSet = new DataSet(items, {
type: {
start: 'Date',
end: 'Date'
}
});
}
// set items
this.itemsData = newDataSet;
this.itemSet && this.itemSet.setItems(newDataSet);
if (initialLoad && ('start' in this.options || 'end' in this.options)) {
this.fit();
var start = ('start' in this.options) ? util.convert(this.options.start, 'Date') : null;
var end = ('end' in this.options) ? util.convert(this.options.end, 'Date') : null;
this.setWindow(start, end);
}
};
/**
* Set groups
* @param {vis.DataSet | Array | google.visualization.DataTable} groups
*/
Timeline.prototype.setGroups = function(groups) {
// convert to type DataSet when needed
var newDataSet;
if (!groups) {
newDataSet = null;
}
else if (groups instanceof DataSet || groups instanceof DataView) {
newDataSet = groups;
}
else {
// turn an array into a dataset
newDataSet = new DataSet(groups);
}
this.groupsData = newDataSet;
this.itemSet.setGroups(newDataSet);
};
/**
* Clear the Timeline. By Default, items, groups and options are cleared.
* Example usage:
*
* timeline.clear(); // clear items, groups, and options
* timeline.clear({options: true}); // clear options only
*
* @param {Object} [what] Optionally specify what to clear. By default:
* {items: true, groups: true, options: true}
*/
Timeline.prototype.clear = function(what) {
// clear items
if (!what || what.items) {
this.setItems(null);
}
// clear groups
if (!what || what.groups) {
this.setGroups(null);
}
// clear options of timeline and of each of the components
if (!what || what.options) {
this.components.forEach(function (component) {
component.setOptions(component.defaultOptions);
});
this.setOptions(this.defaultOptions); // this will also do a redraw
}
};
/**
* Set Timeline window such that it fits all items
*/
Timeline.prototype.fit = function() {
// apply the data range as range
var dataRange = this.getItemRange();
// add 5% space on both sides
var start = dataRange.min;
var end = dataRange.max;
if (start != null && end != null) {
var interval = (end.valueOf() - start.valueOf());
if (interval <= 0) {
// prevent an empty interval
interval = 24 * 60 * 60 * 1000; // 1 day
}
start = new Date(start.valueOf() - interval * 0.05);
end = new Date(end.valueOf() + interval * 0.05);
}
// skip range set if there is no start and end date
if (start === null && end === null) {
return;
}
this.range.setRange(start, end);
};
/**
* Get the data range of the item set.
* @returns {{min: Date, max: Date}} range A range with a start and end Date.
* When no minimum is found, min==null
* When no maximum is found, max==null
*/
Timeline.prototype.getItemRange = function() {
// calculate min from start filed
var dataset = this.itemsData.getDataSet(),
min = null,
max = null;
if (dataset) {
// calculate the minimum value of the field 'start'
var minItem = dataset.min('start');
min = minItem ? util.convert(minItem.start, 'Date').valueOf() : null;
// Note: we convert first to Date and then to number because else
// a conversion from ISODate to Number will fail
// calculate maximum value of fields 'start' and 'end'
var maxStartItem = dataset.max('start');
if (maxStartItem) {
max = util.convert(maxStartItem.start, 'Date').valueOf();
}
var maxEndItem = dataset.max('end');
if (maxEndItem) {
if (max == null) {
max = util.convert(maxEndItem.end, 'Date').valueOf();
}
else {
max = Math.max(max, util.convert(maxEndItem.end, 'Date').valueOf());
}
}
}
return {
min: (min != null) ? new Date(min) : null,
max: (max != null) ? new Date(max) : null
};
};
/**
* Set selected items by their id. Replaces the current selection
* Unknown id's are silently ignored.
* @param {Array} [ids] An array with zero or more id's of the items to be
* selected. If ids is an empty array, all items will be
* unselected.
*/
Timeline.prototype.setSelection = function(ids) {
this.itemSet && this.itemSet.setSelection(ids);
};
/**
* Get the selected items by their id
* @return {Array} ids The ids of the selected items
*/
Timeline.prototype.getSelection = function() {
return this.itemSet && this.itemSet.getSelection() || [];
};
/**
* Set the visible window. Both parameters are optional, you can change only
* start or only end. Syntax:
*
* TimeLine.setWindow(start, end)
* TimeLine.setWindow(range)
*
* Where start and end can be a Date, number, or string, and range is an
* object with properties start and end.
*
* @param {Date | Number | String | Object} [start] Start date of visible window
* @param {Date | Number | String} [end] End date of visible window
*/
Timeline.prototype.setWindow = function(start, end) {
if (arguments.length == 1) {
var range = arguments[0];
this.range.setRange(range.start, range.end);
}
else {
this.range.setRange(start, end);
}
};
/**
* Get the visible window
* @return {{start: Date, end: Date}} Visible range
*/
Timeline.prototype.getWindow = function() {
var range = this.range.getRange();
return {
start: new Date(range.start),
end: new Date(range.end)
};
};
/**
* Force a redraw of the Timeline. Can be useful to manually redraw when
* option autoResize=false
*/
Timeline.prototype.redraw = function() {
var resized = false,
options = this.options,
props = this.props,
dom = this.dom;
if (!dom) return; // when destroyed
// update class names
dom.root.className = 'vis timeline root ' + options.orientation;
// update root width and height options
dom.root.style.maxHeight = util.option.asSize(options.maxHeight, '');
dom.root.style.minHeight = util.option.asSize(options.minHeight, '');
dom.root.style.width = util.option.asSize(options.width, '');
// calculate border widths
props.border.left = (dom.centerContainer.offsetWidth - dom.centerContainer.clientWidth) / 2;
props.border.right = props.border.left;
props.border.top = (dom.centerContainer.offsetHeight - dom.centerContainer.clientHeight) / 2;
props.border.bottom = props.border.top;
var borderRootHeight= dom.root.offsetHeight - dom.root.clientHeight;
var borderRootWidth = dom.root.offsetWidth - dom.root.clientWidth;
// calculate the heights. If any of the side panels is empty, we set the height to
// minus the border width, such that the border will be invisible
props.center.height = dom.center.offsetHeight;
props.left.height = dom.left.offsetHeight;
props.right.height = dom.right.offsetHeight;
props.top.height = dom.top.clientHeight || -props.border.top;
props.bottom.height = dom.bottom.clientHeight || -props.border.bottom;
// TODO: compensate borders when any of the panels is empty.
// apply auto height
// TODO: only calculate autoHeight when needed (else we cause an extra reflow/repaint of the DOM)
var contentHeight = Math.max(props.left.height, props.center.height, props.right.height);
var autoHeight = props.top.height + contentHeight + props.bottom.height +
borderRootHeight + props.border.top + props.border.bottom;
dom.root.style.height = util.option.asSize(options.height, autoHeight + 'px');
// calculate heights of the content panels
props.root.height = dom.root.offsetHeight;
props.background.height = props.root.height - borderRootHeight;
var containerHeight = props.root.height - props.top.height - props.bottom.height -
borderRootHeight;
props.centerContainer.height = containerHeight;
props.leftContainer.height = containerHeight;
props.rightContainer.height = props.leftContainer.height;
// calculate the widths of the panels
props.root.width = dom.root.offsetWidth;
props.background.width = props.root.width - borderRootWidth;
props.left.width = dom.leftContainer.clientWidth || -props.border.left;
props.leftContainer.width = props.left.width;
props.right.width = dom.rightContainer.clientWidth || -props.border.right;
props.rightContainer.width = props.right.width;
var centerWidth = props.root.width - props.left.width - props.right.width - borderRootWidth;
props.center.width = centerWidth;
props.centerContainer.width = centerWidth;
props.top.width = centerWidth;
props.bottom.width = centerWidth;
// resize the panels
dom.background.style.height = props.background.height + 'px';
dom.backgroundVertical.style.height = props.background.height + 'px';
dom.backgroundHorizontal.style.height = props.centerContainer.height + 'px';
dom.centerContainer.style.height = props.centerContainer.height + 'px';
dom.leftContainer.style.height = props.leftContainer.height + 'px';
dom.rightContainer.style.height = props.rightContainer.height + 'px';
dom.background.style.width = props.background.width + 'px';
dom.backgroundVertical.style.width = props.centerContainer.width + 'px';
dom.backgroundHorizontal.style.width = props.background.width + 'px';
dom.centerContainer.style.width = props.center.width + 'px';
dom.top.style.width = props.top.width + 'px';
dom.bottom.style.width = props.bottom.width + 'px';
// reposition the panels
dom.background.style.left = '0';
dom.background.style.top = '0';
dom.backgroundVertical.style.left = props.left.width + 'px';
dom.backgroundVertical.style.top = '0';
dom.backgroundHorizontal.style.left = '0';
dom.backgroundHorizontal.style.top = props.top.height + 'px';
dom.centerContainer.style.left = props.left.width + 'px';
dom.centerContainer.style.top = props.top.height + 'px';
dom.leftContainer.style.left = '0';
dom.leftContainer.style.top = props.top.height + 'px';
dom.rightContainer.style.left = (props.left.width + props.center.width) + 'px';
dom.rightContainer.style.top = props.top.height + 'px';
dom.top.style.left = props.left.width + 'px';
dom.top.style.top = '0';
dom.bottom.style.left = props.left.width + 'px';
dom.bottom.style.top = (props.top.height + props.centerContainer.height) + 'px';
// update the scrollTop, feasible range for the offset can be changed
// when the height of the Timeline or of the contents of the center changed
this._updateScrollTop();
// reposition the scrollable contents
var offset = this.props.scrollTop;
if (options.orientation == 'bottom') {
offset += Math.max(this.props.centerContainer.height - this.props.center.height -
this.props.border.top - this.props.border.bottom, 0);
}
dom.center.style.left = '0';
dom.center.style.top = offset + 'px';
dom.left.style.left = '0';
dom.left.style.top = offset + 'px';
dom.right.style.left = '0';
dom.right.style.top = offset + 'px';
// show shadows when vertical scrolling is available
var visibilityTop = this.props.scrollTop == 0 ? 'hidden' : '';
var visibilityBottom = this.props.scrollTop == this.props.scrollTopMin ? 'hidden' : '';
dom.shadowTop.style.visibility = visibilityTop;
dom.shadowBottom.style.visibility = visibilityBottom;
dom.shadowTopLeft.style.visibility = visibilityTop;
dom.shadowBottomLeft.style.visibility = visibilityBottom;
dom.shadowTopRight.style.visibility = visibilityTop;
dom.shadowBottomRight.style.visibility = visibilityBottom;
// redraw all components
this.components.forEach(function (component) {
resized = component.redraw() || resized;
});
if (resized) {
// keep repainting until all sizes are settled
this.redraw();
}
};
// TODO: deprecated since version 1.1.0, remove some day
Timeline.prototype.repaint = function () {
throw new Error('Function repaint is deprecated. Use redraw instead.');
};
/**
* Convert a position on screen (pixels) to a datetime
* @param {int} x Position on the screen in pixels
* @return {Date} time The datetime the corresponds with given position x
* @private
*/
// TODO: move this function to Range
Timeline.prototype._toTime = function(x) {
var conversion = this.range.conversion(this.props.center.width);
return new Date(x / conversion.scale + conversion.offset);
};
/**
* Convert a position on the global screen (pixels) to a datetime
* @param {int} x Position on the screen in pixels
* @return {Date} time The datetime the corresponds with given position x
* @private
*/
// TODO: move this function to Range
Timeline.prototype._toGlobalTime = function(x) {
var conversion = this.range.conversion(this.props.root.width);
return new Date(x / conversion.scale + conversion.offset);
};
/**
* Convert a datetime (Date object) into a position on the screen
* @param {Date} time A date
* @return {int} x The position on the screen in pixels which corresponds
* with the given date.
* @private
*/
// TODO: move this function to Range
Timeline.prototype._toScreen = function(time) {
var conversion = this.range.conversion(this.props.center.width);
return (time.valueOf() - conversion.offset) * conversion.scale;
};
/**
* Convert a datetime (Date object) into a position on the root
* This is used to get the pixel density estimate for the screen, not the center panel
* @param {Date} time A date
* @return {int} x The position on root in pixels which corresponds
* with the given date.
* @private
*/
// TODO: move this function to Range
Timeline.prototype._toGlobalScreen = function(time) {
var conversion = this.range.conversion(this.props.root.width);
return (time.valueOf() - conversion.offset) * conversion.scale;
};
/**
* Initialize watching when option autoResize is true
* @private
*/
Timeline.prototype._initAutoResize = function () {
if (this.options.autoResize == true) {
this._startAutoResize();
}
else {
this._stopAutoResize();
}
};
/**
* Watch for changes in the size of the container. On resize, the Panel will
* automatically redraw itself.
* @private
*/
Timeline.prototype._startAutoResize = function () {
var me = this;
this._stopAutoResize();
this._onResize = function() {
if (me.options.autoResize != true) {
// stop watching when the option autoResize is changed to false
me._stopAutoResize();
return;
}
if (me.dom.root) {
// check whether the frame is resized
if ((me.dom.root.clientWidth != me.props.lastWidth) ||
(me.dom.root.clientHeight != me.props.lastHeight)) {
me.props.lastWidth = me.dom.root.clientWidth;
me.props.lastHeight = me.dom.root.clientHeight;
me.emit('change');
}
}
};
// add event listener to window resize
util.addEventListener(window, 'resize', this._onResize);
this.watchTimer = setInterval(this._onResize, 1000);
};
/**
* Stop watching for a resize of the frame.
* @private
*/
Timeline.prototype._stopAutoResize = function () {
if (this.watchTimer) {
clearInterval(this.watchTimer);
this.watchTimer = undefined;
}
// remove event listener on window.resize
util.removeEventListener(window, 'resize', this._onResize);
this._onResize = null;
};
/**
* Start moving the timeline vertically
* @param {Event} event
* @private
*/
Timeline.prototype._onTouch = function (event) {
this.touch.allowDragging = true;
};
/**
* Start moving the timeline vertically
* @param {Event} event
* @private
*/
Timeline.prototype._onPinch = function (event) {
this.touch.allowDragging = false;
};
/**
* Start moving the timeline vertically
* @param {Event} event
* @private
*/
Timeline.prototype._onDragStart = function (event) {
this.touch.initialScrollTop = this.props.scrollTop;
};
/**
* Move the timeline vertically
* @param {Event} event
* @private
*/
Timeline.prototype._onDrag = function (event) {
// refuse to drag when we where pinching to prevent the timeline make a jump
// when releasing the fingers in opposite order from the touch screen
if (!this.touch.allowDragging) return;
var delta = event.gesture.deltaY;
var oldScrollTop = this._getScrollTop();
var newScrollTop = this._setScrollTop(this.touch.initialScrollTop + delta);
if (newScrollTop != oldScrollTop) {
this.redraw(); // TODO: this causes two redraws when dragging, the other is triggered by rangechange already
}
};
/**
* Apply a scrollTop
* @param {Number} scrollTop
* @returns {Number} scrollTop Returns the applied scrollTop
* @private
*/
Timeline.prototype._setScrollTop = function (scrollTop) {
this.props.scrollTop = scrollTop;
this._updateScrollTop();
return this.props.scrollTop;
};
/**
* Update the current scrollTop when the height of the containers has been changed
* @returns {Number} scrollTop Returns the applied scrollTop
* @private
*/
Timeline.prototype._updateScrollTop = function () {
// recalculate the scrollTopMin
var scrollTopMin = Math.min(this.props.centerContainer.height - this.props.center.height, 0); // is negative or zero
if (scrollTopMin != this.props.scrollTopMin) {
// in case of bottom orientation, change the scrollTop such that the contents
// do not move relative to the time axis at the bottom
if (this.options.orientation == 'bottom') {
this.props.scrollTop += (scrollTopMin - this.props.scrollTopMin);
}
this.props.scrollTopMin = scrollTopMin;
}
// limit the scrollTop to the feasible scroll range
if (this.props.scrollTop > 0) this.props.scrollTop = 0;
if (this.props.scrollTop < scrollTopMin) this.props.scrollTop = scrollTopMin;
return this.props.scrollTop;
};
/**
* Get the current scrollTop
* @returns {number} scrollTop
* @private
*/
Timeline.prototype._getScrollTop = function () {
return this.props.scrollTop;
};