The Timeline is an interactive visualization chart to visualize data in time. The data items can take place on a single date, or have a start and end date (a range). You can freely move and zoom in the timeline by dragging and scrolling in the Timeline. Items can be created, edited, and deleted in the timeline. The time scale on the axis is adjusted automatically, and supports scales ranging from milliseconds to years.
Timeline uses regular HTML DOM to render the timeline and items put on the timeline. This allows for flexible customization using css styling.
The following code shows how to create a Timeline and provide it with data. More examples can be found in the examples directory.
<!DOCTYPE HTML> <html> <head> <title>Timeline | Basic demo</title> <style type="text/css"> body, html { font-family: sans-serif; } </style> <script src="../../dist/vis.js"></script> <link href="../../dist/vis.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="visualization"></div> <script type="text/javascript"> // DOM element where the Timeline will be attached var container = document.getElementById('visualization'); // Create a DataSet (allows two way data-binding) var items = new vis.DataSet([ {id: 1, content: 'item 1', start: '2013-04-20'}, {id: 2, content: 'item 2', start: '2013-04-14'}, {id: 3, content: 'item 3', start: '2013-04-18'}, {id: 4, content: 'item 4', start: '2013-04-16', end: '2013-04-19'}, {id: 5, content: 'item 5', start: '2013-04-25'}, {id: 6, content: 'item 6', start: '2013-04-27'} ]); // Configuration for the Timeline var options = {}; // Create a Timeline var timeline = new vis.Timeline(container, items, options); </script> </body> </html>
Install or download the vis.js library. in a subfolder of your project. Include the libraries script and css files in the head of your html code:
<script src="vis/dist/vis.js"></script> <link href="vis/dist/vis.css" rel="stylesheet" type="text/css" />The constructor of the Timeline is
vis.Timeline
var timeline = new vis.Timeline(container, items, options);or when using groups:
var timeline = new vis.Timeline(container, items, groups, options);The constructor accepts four parameters:
container
is the DOM element in which to create the timeline.
items
is an Array containing items. The properties of an
item are described in section Data Format, items.
groups
is an Array containing groups. The properties of a
group are described in section Data Format, groups.
options
is an optional Object containing a name-value map
with options. Options can also be set using the method
setOptions
.
The timeline can be provided with two types of data:
The Timeline uses regular Arrays and Objects as data format.
Data items can contain the properties start
,
end
(optional), content
,
group
(optional), className
(optional),
and style
(optional).
A table is constructed as:
var items = [ { start: new Date(2010, 7, 15), end: new Date(2010, 8, 2), // end is optional content: 'Trajectory A' // Optional: fields 'id', 'type', 'group', 'className', 'style' } // more items... ]);
The item properties are defined as:
Name | Type | Required | Description |
className | String | no | This field is optional. A className can be used to give items
an individual css style. For example, when an item has className
'red', one can define a css style like:
.vis.timeline .red { color: white; background-color: red; border-color: darkred; }More details on how to style items can be found in the section Styles. |
content | String | yes | The contents of the item. This can be plain text or html code. |
end | Date | number | string | Moment | no | The end date of the item. The end date is optional, and can be left null .
If end date is provided, the item is displayed as a range.
If not, the item is displayed as a box. |
group | any type | no | This field is optional. When the group column is provided,
all items with the same group are placed on one line.
A vertical axis is displayed showing the groups.
Grouping items can be useful for example when showing availability of multiple
people, rooms, or other resources next to each other. |
id | String | Number | no | An id for the item. Using an id is not required but highly recommended. An id is needed when dynamically adding, updating, and removing items in a DataSet. |
start | Date | number | string | Moment | yes | The start date of the item, for example new Date(2010,9,23) . |
style | String | no |
A css text string to apply custom styling for an individual item, for
example "color: red; background-color: pink;" .
|
subgroup | String | Number | none | The id of a subgroup.
Groups all items within a group per subgroup, and positions them on the
same height instead of staking them on top of each other. can be ordered
by specifying the option subgroupOrder of a group.
|
title | String | none | Add a title for the item, displayed when holding the mouse on the item. The title can only contain plain text. |
type | String | no | The type of the item. Can be 'box' (default), 'point', 'range', or 'background'. Types 'box' and 'point' need a start date, the types 'range' and 'background' needs both a start and end date. |
Like the items, groups are regular JavaScript Arrays and Objects.
Using groups, items can be grouped together.
Items are filtered per group, and displayed as
Group items can contain the properties id
,
content
, and className
(optional).
Groups can be applied to a timeline using the method setGroups
or supplied in the constructor.
A table with groups can be created like:
var groups = [ { id: 1, content: 'Group 1' // Optional: a field 'className', 'style' } // more groups... ]);
Groups can have the following properties:
Name | Type | Required | Description |
className | String | no | This field is optional. A className can be used to give groups
an individual css style. For example, when a group has className
'red', one can define a css style
.red {
color: red;
}
.
More details on how to style groups can be found in the section
Styles.
|
content | String | yes | The contents of the group. This can be plain text or html code. |
id | String | Number | yes | An id for the group. The group will display all items having a
property group which matches the id
of the group. |
style | String | no |
A css text string to apply custom styling for an individual group label, for
example "color: red; background-color: pink;" .
|
subgroupOrder | String | Function | none | Order the subgroups by a field name or custom sort function. By default, groups are ordered by first-come, first-show. |
title | String | none | A title for the group, displayed when holding the mouse on the groups label. The title can only contain plain text. |
Options can be used to customize the timeline. Options are defined as a JSON object. All options are optional.
var options = { width: '100%', height: '30px', margin: { item: 20 } };
The following options are available.
Name | Type | Default | Description |
align | String | 'center' |
Alignment of items with type 'box', 'range', and 'background'. Available values are 'auto' (default), 'center', 'left', or 'right'. For 'box' items, the 'auto' alignment is 'center'. For 'range' items, the auto alignment is dynamic: positioned left and shifted such that the contents is always visible on screen. |
autoResize | boolean | true |
If true, the Timeline will automatically detect when its container is resized, and redraw itself accordingly. If false, the Timeline can be forced to repaint after its container has been resized using the function redraw() . |
clickToUse | boolean | false |
When a Timeline is configured to be clickToUse , it will react to mouse and touch events only when active.
When active, a blue shadow border is displayed around the Timeline. The Timeline is set active by clicking on it, and is changed to inactive again by clicking outside the Timeline or by pressing the ESC key. |
dataAttributes | string[] | 'all' | false |
An array of fields optionally defined on the timeline items that will be appended as data- attributes to the DOM element of the items.If value is 'all' then each field defined on the timeline item will become a data- attribute. |
editable | boolean | Object | false |
If true, the items in the timeline can be manipulated. Only applicable when option selectable is . See also the callbacks onAdd , onUpdate , onMove , and onRemove . When editable is an object, one can enable or disable individual manipulation actions.
See section Editing Items for a detailed explanation.
|
editable.add | boolean | false |
If true, new items can be created by double tapping an empty space in the Timeline. See section Editing Items for a detailed explanation. |
editable.remove | boolean | false |
If true, items can be deleted by first selecting them, and then clicking the delete button on the top right of the item. See section Editing Items for a detailed explanation. |
editable.updateGroup | boolean | false |
If true, items can be dragged from one group to another. Only applicable when the Timeline has groups. See section Editing Items for a detailed explanation. |
editable.updateTime | boolean | false |
If true, items can be dragged to another moment in time. See section Editing Items for a detailed explanation. |
end | Date | Number | String | Moment | none | The initial end date for the axis of the timeline. If not provided, the latest date present in the items set is taken as end date. |
format | Object | none |
Apply custom date formatting of the labels on the time axis. The default value of format is:
{ minorLabels: { millisecond:'SSS', second: 's', minute: 'HH:mm', hour: 'HH:mm', weekday: 'ddd D', day: 'D', month: 'MMM', year: 'YYYY' }, majorLabels: { millisecond:'HH:mm:ss', second: 'D MMMM HH:mm', minute: 'ddd D MMMM', hour: 'ddd D MMMM', weekday: 'MMMM YYYY', day: 'MMMM YYYY', month: 'YYYY', year: '' } }For values which not provided in the customized options.format , the default values will be used.
All available formatting syntax is described in the docs of moment.js.
|
groupOrder | String | Function | none | Order the groups by a field name or custom sort function. By default, groups are not ordered. |
height | number | String | none | The height of the timeline in pixels or as a percentage.
When height is undefined or null, the height of the timeline is automatically
adjusted to fit the contents.
It is possible to set a maximum height using option maxHeight
to prevent the timeline from getting too high in case of automatically
calculated height.
|
hiddenDates | Object | none | This option allows you to hide specific timespans from the time axis. The dates can be supplied as an object:
{start: '2014-03-21 00:00:00', end: '2014-03-28 00:00:00', [repeat:'daily']} or as an Array of these objects. The repeat argument is optional.
The possible values are (case-sensitive): daily, weekly, monthly, yearly . To hide a weekend, pick any Saturday as start and the following Monday as end
and set repeat to weekly.
|
locale | String | none | Select a locale for the Timeline. See section Localization for more information. |
locales | Object | none | A map with i18n locales. See section Localization for more information. |
margin | number | Object | Object | When a number, applies the margin to margin.axis , margin.item.horizontal , and margin.item.vertical . |
margin.axis | number | 20 |
The minimal margin in pixels between items and the time axis. |
margin.item | number | 10 |
The minimal margin in pixels between items in both horizontal and vertical direction. |
margin.item.horizontal | number | 10 |
The minimal horizontal margin in pixels between items. |
margin.item.vertical | number | 10 |
The minimal vertical margin in pixels between items. |
max | Date | Number | String | Moment | none | Set a maximum Date for the visible range. It will not be possible to move beyond this maximum. |
maxHeight | number | String | none | Specifies the maximum height for the Timeline. Can be a number in pixels or a string like "300px". |
min | Date | Number | String | Moment | none | Set a minimum Date for the visible range. It will not be possible to move beyond this minimum. |
minHeight | number | String | none | Specifies the minimum height for the Timeline. Can be a number in pixels or a string like "300px". |
moveable | boolean | true |
Specifies whether the Timeline can be moved and zoomed by dragging the window.
See also option zoomable .
|
onAdd | function | none | Callback function triggered when an item is about to be added: when the user double taps an empty space in the Timeline. See section Editing Items for more information. Only applicable when both options selectable and editable.add are set .
|
onUpdate | function | none | Callback function triggered when an item is about to be updated, when the user double taps an item in the Timeline. See section Editing Items for more information. Only applicable when both options selectable and editable.updateTime or editable.updateGroup are set .
|
onMove | function | none | Callback function triggered when an item has been moved: after the user has dragged the item to an other position. See section Editing Items for more information. Only applicable when both options selectable and editable.updateTime or editable.updateGroup are set .
|
onMoving | function | none | Callback function triggered repeatedly when an item is being moved. See section Editing Items for more information. Only applicable when both options selectable and editable.updateTime or editable.updateGroup are set .
|
onRemove | function | none | Callback function triggered when an item is about to be removed: when the user tapped the delete button on the top right of a selected item. See section Editing Items for more information. Only applicable when both options selectable and editable.remove are set .
|
order | function | none |
Provide a custom sort function to order the items. The order of the items is determining the way they are stacked. The function order is called with two arguments containing the data of two items to be compared. WARNING: Use with caution. Custom ordering is not suitable for large amounts of items. On load, the Timeline will render all items once to determine their width and height. Keep the number of items in this configuration limited to a maximum of a few hundred items. |
orientation | String | Object | 'bottom' |
Orientation of the timelines axis and items. When orientation is a string, the value is applied to both items and axis. Can be 'top', 'bottom' (default), or 'both'. |
orientation.axis | String | 'bottom' |
Orientation of the timeline axis: 'top', 'bottom' (default), or 'both'. If orientation is 'bottom', the time axis is drawn at the bottom. When 'top', the axis is drawn on top. When 'both', two axes are drawn, both on top and at the bottom. |
orientation.item | String | 'bottom' |
Orientation of the timeline items: 'top' or 'bottom' (default). Determines whether items are aligned to the top or bottom of the Timeline. |
selectable | boolean | true |
If true, the items on the timeline can be selected. Multiple items can be selected by long pressing them, or by using ctrl+click or shift+click. The event select is fired each time the selection has changed (see section Events). |
showCurrentTime | boolean | true |
Show a vertical bar at the current time. |
showMajorLabels | boolean | true |
By default, the timeline shows both minor and major date labels on the
time axis.
For example the minor labels show minutes and the major labels show hours.
When showMajorLabels is , no major labels
are shown. |
showMinorLabels | boolean | true |
By default, the timeline shows both minor and major date labels on the
time axis.
For example the minor labels show minutes and the major labels show hours.
When showMinorLabels is , no minor labels
are shown. When both showMajorLabels and
showMinorLabels are false, no horizontal axis will be
visible. |
stack | boolean | true |
If true (default), items will be stacked on top of each other such that they do not overlap. |
snap | function | null | function | When moving items on the Timeline, they will be snapped to nice dates like full hours or days, depending on the current scale. The snap function can be replaced with a custom function, or can be set to null to disable snapping. The signature of the snap function is:
function snap(date: Date, scale: string, step: number) : Date | numberThe parameter scale can be can be 'millisecond', 'second', 'minute', 'hour', 'weekday, 'day, 'month, or 'year'. The parameter step is a number like 1, 2, 4, 5.
|
start | Date | Number | String | Moment | none | The initial start date for the axis of the timeline. If not provided, the earliest date present in the events is taken as start date. |
template | function | none | A template function used to generate the contents of the items. The function is called by the Timeline with an items data as argument, and must return HTML code as result. When the option template is specified, the items do not need to have a field content . See section Templates for a detailed explanation. |
timeAxis | Object | Object |
Specify a fixed scale and step size for the time axis. |
timeAxis.scale | String | none | Set a fixed scale for the time axis of the Timeline. Choose from 'millisecond' , 'second' , 'minute' , 'hour' , 'weekday' , 'day' , 'month' , 'year' . Example usage:
var options = { timeAxis: {scale: 'minute', step: 5} } |
timeAxis.step | number | 1 |
Set a fixed step size for the time axis. Only applicable when used together with timeAxis.scale .
Choose for example 1, 2, 5, or 10. |
type | String | none | Specifies the default type for the timeline items. Choose from 'box', 'point', 'range', and 'background'. Note that individual items can override this default type. If undefined, the Timeline will auto detect the type from the items data: if a start and end date is available, a 'range' will be created, and else, a 'box' is created. Items of type 'background' are not editable. |
width | String | '100%' |
The width of the timeline in pixels or as a percentage. |
zoomable | boolean | true |
Specifies whether the Timeline can be zoomed by pinching or scrolling in the window.
Only applicable when option moveable is set .
|
zoomMax | number | 315360000000000 |
Set a maximum zoom interval for the visible range in milliseconds. It will not be possible to zoom out further than this maximum. Default value equals about 10000 years. |
zoomMin | number | 10 |
Set a minimum zoom interval for the visible range in milliseconds. It will not be possible to zoom in further than this minimum. |
The Timeline supports the following methods.
Method | Return Type | Description |
addCustomTime([time] [, id]) | number | String |
Add new vertical bar representing a custom time that can be dragged by the user.
Parameter time can be a Date, Number, or String, and is new Date() by default.
Parameter id can be Number or String and is undefined by default.Returns id of the created bar. |
destroy() | none | Destroy the Timeline. The timeline is removed from memory. all DOM elements and event listeners are cleaned up. |
fit([options]) | none | Adjust the visible window such that it fits all items. See also function focus(id) .
Available options:
|
focus(id | ids [, options]) | none | Adjust the visible window such that the selected item (or multiple items) are centered on screen. See also function fit() . Available options:
|
getCurrentTime() | Date | Get the current time. Only applicable when option showCurrentTime is true.
|
getCustomTime([id]) | Date | Retrieve the custom time from the custom time bar with given id. Id is undefined by default.
|
getEventProperties(event) | Object |
Returns an Object with relevant properties from an event:
|
getSelection() | number[] | Get an array with the ids of the currently selected items. |
getVisibleItems() | number[] | Get an array with the ids of the currently visible items. |
getWindow() | Object | Get the current visible window. Returns an object with properties start: Date and end: Date . |
moveTo(time [, options]) | none | Move the window such that given time is centered on screen. Parameter time can be a Date , Number , or String . Available options:
|
on(event, callback) | none | Create an event listener. The callback function is invoked every time the event is triggered. Avialable events: rangechange , rangechanged , select . The callback function is invoked as callback(properties) , where properties is an object containing event specific properties. See section Events for more information. |
off(event, callback) | none | Remove an event listener created before via function on(event, callback) . See section Events for more information. |
redraw() | none | Force a redraw of the Timeline. The size of all items will be recalculated.
Can be useful to manually redraw when option autoResize=false and the window
has been resized, or when the items CSS has been changed.
|
removeCustomTime(id) | none |
Remove vertical bars previously added to the timeline via addCustomTime method. Parameter id is the ID of the custom vertical bar returned by addCustomTime method.
|
setCurrentTime(time) | none | Set a current time. This can be used for example to ensure that a client's time is synchronized with a shared server time.
time can be a Date object, numeric timestamp, or ISO date string.
Only applicable when option showCurrentTime is true. |
setCustomTime(time [, id]) | none | Adjust the time of a custom time bar.
Parameter time can be a Date object, numeric timestamp, or ISO date string.
Parameter id is the idof the custom time bar, and is undefined by default.
|
setData({ groups: groups, items: items }) |
none | Set both groups and items at once. Both properties are optional. This is a convenience method for individually calling both setItems(items) and setGroups(groups) .
Both items and groups can be an Array with Objects,
a DataSet, or a DataView. For each of the groups, the items of the
timeline are filtered on the property group , which
must correspond with the id of the group.
|
setGroups(groups) | none | Set a data set with groups for the Timeline.
groups can be an Array with Objects,
a DataSet, or a DataView. For each of the groups, the items of the
timeline are filtered on the property group , which
must correspond with the id of the group.
|
setItems(items) | none | Set a data set with items for the Timeline.
items can be an Array with Objects,
a DataSet, or a DataView.
|
setOptions(options) | none | Set or update options. It is possible to change any option of the timeline at any time. You can for example switch orientation on the fly. |
setSelection(id | ids [, options]) | none | Select one or multiple items by their id. The currently selected items will be unselected. To unselect all selected items, call `setSelection([])`. Available options:
|
setWindow(start, end [, options]) | none | Set the current visible window. The parameters start and end can be a Date , Number , or String . If the parameter value of start or end is null, the parameter will be left unchanged. Available options:
|
Timeline fires events when changing the visible window by dragging, when selecting items, and when dragging the custom time bar.
Here an example on how to listen for a select
event.
timeline.on('select', function (properties) { alert('selected items: ' + properties.nodes); });
A listener can be removed via the function off
:
function onSelect (properties) { alert('selected items: ' + properties.nodes); } // add event listener timeline.on('select', onSelect); // do stuff... // remove event listener timeline.off('select', onSelect);
The following events are available.
name | Description | Properties |
click | Fired when clicked inside the Timeline. |
Passes a properties object as returned by the method Timeline.getEventProperties(event) .
|
contextmenu | Fired when right-clicked inside the Timeline. Note that in order to prevent the context menu from showing up, default behavior of the event must be stopped:
timeline.on('contextmenu', function (props) { alert('Right click!'); props.event.preventDefault(); }); |
Passes a properties object as returned by the method Timeline.getEventProperties(event) .
|
doubleClick | Fired when double clicked inside the Timeline. |
Passes a properties object as returned by the method Timeline.getEventProperties(event) .
|
rangechange | Fired repeatedly when the timeline window is being changed. |
|
rangechanged | Fired once after the timeline window has been changed. |
|
select | Fired after the user selects or deselects items by tapping or holding them.
When a use taps an already selected item, the select event is fired again.
Not fired when the method setSelection is executed.
|
|
timechange | Fired repeatedly when the user is dragging the custom time bar. Only available when the custom time bar is enabled. |
|
timechanged | Fired once after the user has dragged the custom time bar. Only available when the custom time bar is enabled. |
|
When the Timeline is configured to be editable (both options selectable
and editable
are
), the user can:
true
Option editable
accepts a boolean or an object. When editable
is a boolean, all manipulation actions will be either enabled or disabled. When editable
is an object, one can enable individual manipulation actions:
// enable or disable all manipulation actions var options = { editable: true // true or false }; // enable or disable individual manipulation actions var options = { editable: { add: true, // add new items by double tapping updateTime: true, // drag items horizontally updateGroup: true, // drag items from one group to another remove: true // delete an item by tapping the delete button top right } };
One can specify callback functions to validate changes made by the user. There are a number of callback functions for this purpose:
onAdd(item, callback)
Fired when a new item is about to be added. If not implemented, the item will be added with default text contents.onUpdate(item, callback)
Fired when an item is about to be updated. This function typically has to show a dialog where the user change the item. If not implemented, nothing happens.onMove(item, callback)
Fired when an item has been moved. If not implemented, the move action will be accepted.onMoving(item, callback)
Fired repeatedly while an item is being moved (dragged). Can be used to adjust the items start, end, and/or group to allowed regions.onRemove(item, callback)
Fired when an item is about to be deleted. If not implemented, the item will be always removed.Each of the callbacks is invoked with two arguments:
item
: the item being manipulatedcallback
: a callback function which must be invoked to report back. The callback must be invoked as callback(item | null)
. Here, item
can contain changes to the passed item. Parameter `item` typically contains fields `content`, `start`, and optionally `end`. The type of `start` and `end` is determined by the DataSet type configuration and is `Date` by default. When invoked as callback(null)
, the action will be cancelled.Example code:
var options = { onUpdate: function (item, callback) { item.content = prompt('Edit items text:', item.content); if (item.content != null) { callback(item); // send back adjusted item } else { callback(null); // cancel updating the item } } };A full example is available here: 08_manipulation_callbacks.html.
Timeline supports templates to format item contents. Any template engine (such as handlebars or mustache) can be used, and one can also manually build HTML. In the options, one can provide a template handler. This handler is a function accepting an items data as argument, and outputs formatted HTML:
var options = { template: function (item) { var html = ... // generate HTML markup for this item return html; } };
var options = { template: function (item) { return '<h1>' + item.header + '</h1><p>' + item.description + '</p>'; } };
<script id="item-template" type="text/x-handlebars-template"> <h1>{{header}}</h1> <p>{{description}}</p> </script>Compile the template:
var source = document.getElementById('item-template').innerHTML; var template = Handlebars.compile(source);And then specify the template in the Timeline options
var options = { template: template };
var templates = { template1: Handlebars.compile(...), template2: Handlebars.compile(...), template2: Handlebars.compile(...), ... }; var options = { template: function (item) { var template = templates[item.template]; // choose the right template return template(item); // execute the template } };Now the items can be extended with a property
template
, specifying which template to use for the item.
Timeline can be localized. For localization, Timeline depends largely on the localization of moment.js. Locales are not included in vis.js by default. To enable localization, moment.js must be loaded with locales. Moment.js offers a bundle named "moment-with-locales.min.js" for this and there are various alternative ways to load locales.
To set a locale for the Timeline, specify the option locale
:
var options = { locale: 'nl' };
locales
:
var options = { locales: { // create a new locale (text strings should be replaced with localized strings) mylocale: { current: 'current', time: 'time', } }, // use the new locale locale: 'mylocale' };
Timeline comes with support for the following locales:
Language | Code |
English |
en en_EN en_US
|
Dutch |
nl nl_NL nl_BE
|
All parts of the Timeline have a class name and a default css style. The styles can be overwritten, which enables full customization of the layout of the Timeline.
For example, to change the border and background color of all items, include the following code inside the head of your html code or in a separate stylesheet.
<style> .vis-item { border-color: orange; background-color: yellow; } </style>
The background grid of the time axis can be styled, for example to highlight weekends or to create grids with an alternating white/lightgray background.
Depending on the zoom level, the grids get certain css classes attached. The following classes are available:
Description | values |
Alternating columns | even , odd |
Current date | today , tomorrow , yesterday , current-week , current-month , current-year |
Hours | h0 , h1 , ..., h23 |
Grouped hours | h0-h4 to h20-h24 |
Weekday | monday , tuesday , wednesday , thursday , friday , saturday , sunday |
Days | date1 , date2 , ..., date31 |
Months | januari , februari , march , april , may , june , july , august , september , october , november , december |
Years | year2014 , year2015 , ... |
Examples:
<style> /* alternating column backgrounds */ .vis-time-axis .grid.odd { background: #f5f5f5; } /* gray background in weekends, white text color */ .vis-time-axis .vis-grid.saturday, .vis-time-axis .vis-grid.sunday { background: gray; } .vis-time-axis .vis-text.saturday, .vis-time-axis .vis-text.sunday { color: white; } </style>
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