设置过去的背景颜色

Question

我希望能够灰化vis.js时间线的过去。我能够显示它：

var container = document.getElementById('visualization'); 
 

 
var items = new vis.DataSet([]); 
 

 
var timeline = new vis.Timeline(container, items, {});

<script src="http://visjs.org/dist/vis.js"></script> 
 
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/vis/4.14.0/vis.css"> 
 
<p> 
 
    A basic timeline. You can move and zoom the timeline, and select items. 
 
</p> 
 

 
<div id="visualization"></div>

但我不能找到像在the docvis-past任何类来设置背景色。

我想实现这一点：

Answer 1

以备将来参考，只需创建一个没有内容的项目，在最短的日期为起点，现在作为结束：

{id: 'past', content: '', start: new Date(-8640000000000000), end: Date(), type: 'background'} 

这是，工作：

var container = document.getElementById('visualization'); 
 

 
var items = new vis.DataSet([{id: 'past', content: '', start: new Date(-8640000000000000), end: Date(), type: 'background'}]); 
 

 
var options = { 
 
    start: '2016-01-01', 
 
    end: '2016-04-01', 
 
    editable: false 
 
    }; 
 

 
var timeline = new vis.Timeline(container, items, options);

.vis-item.vis-background { 
 
    background-color: rgba(222,222,222,0.5) !important; 
 
} 
 

 
body{ 
 
    background-color:white; 
 
}

<script src="http://visjs.org/dist/vis.js"></script> 
 
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/vis/4.14.0/vis.css"> 
 

 
<div id="visualization"></div>