需要在子图选择上显示 X 轴标签

Question

c3js.org/samples/options_subchart 显示问题：当通过子图表选择的窗口导航时，x 刻度没有标签。

在这个动态窗口视图中如何添加 x 轴标签？

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注意事项

这是没有选择窗口的图表，

这是选择了一个窗口的图表：

看到了吗？ 没有 x 轴标签，即使每个点都存在（在这种情况下是不同的一天）。

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使用@schustischuster 的示例进行编辑（通过更多数据增强）http://jsfiddle.net/xodyq92n/

 // more x-axis data to show the problem
 ['x', '2013-01-01', '2013-01-02', '2013-01-03', '2013-01-04',
       '2013-01-05', '2013-01-06', '2013-01-07', '2013-01-08',
       '2013-01-09', '2013-01-10', '2013-01-11', '2013-01-12',
       '2013-01-13'
 ]

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注意@buræquete 关于culling: false 和子图表控件的线索后onbrush。我的现实生活中的数据有大约 600 个 x 轴项，所以不剔除会导致很大的模糊：

那么，问题可以概括为需要“中间剔除”。

Answer 1

previous solution with culling turned off

我没有关闭culling，然后删除多余的标签，而是保持启用它，并在放大时强制在主图表中显示标签。这可以在this fiddle上查看。

或者查看下面的sn-p；

const TICK_WIDTH = 35;
var chart = document.getElementById("c3_chart");
var visibilityThreshold = chart.clientWidth / TICK_WIDTH;

function addLabelToTicks() {
  var allTicks = document.querySelectorAll("#c3_chart .c3-axis-x.c3-axis > g");
  var visibleTicks = Array.from(allTicks)
    .filter(tick => !tick.querySelector("line[x1='0'][x2='0'][y2='0']"));
  if (visibleTicks.length < visibilityThreshold) {
    visibleTicks.forEach(tick => tick.querySelector("text").style.display = "block");
  }
}

var chart = c3.generate({
  bindto: '#c3_chart',
  data: {
    x: 'x',
    //        xFormat: '%Y%m%d', // 'xFormat' can be used as custom format of 'x'
    columns: [
      ['x', '2013-01-01', '2013-01-02', '2013-01-03', '2013-01-04', '2013-01-05', '2013-01-06',
        '2013-01-07', '2013-01-08', '2013-01-09', '2013-01-10', '2013-01-11', '2013-01-12', '2013-01-13', '2013-01-14', '2013-01-15', '2013-01-16', '2013-01-17', '2013-01-18', '2013-01-19',
        '2013-01-20', '2013-01-21', '2013-01-22', '2013-01-23', '2013-01-24', '2013-01-25', '2013-01-26'
      ],
      ['data1', 30, 200, 100, 400, 150, 250, 160, 150, 160, 150, 200, 160, 170, 30, 200, 100, 400, 150, 250, 160, 150, 160, 150, 200, 160, 170],
      ['data2', 130, 340, 200, 500, 250, 350, 320, 200, 500, 250, 350, 300, 310, 130, 340, 200, 500, 250, 350, 320, 200, 500, 250, 350, 300, 310]
    ]
  },
  subchart: {
    show: true,
    onbrush: addLabelToTicks
  },
  axis: {
    x: {
      type: 'timeseries',
      tick: {
        rotate: 25,
        //culling: false,
        format: '%Y-%m-%d'
      }
    }
  }
});

.c3 svg {
  font: 10px sans-serif
}

.c3 line,
.c3 path {
  fill: none;
  stroke: #000;
}


/* In this example I changed the line color to red for c3_chart_2 */

#c3_chart_2.c3 line,
#c3_chart_2.c3 path {
  fill: none;
  stroke: red;
}

.c3 text {
  -webkit-user-select: none;
  -moz-user-select: none;
  user-select: none
}

.c3-bars path,
.c3-event-rect,
.c3-legend-item-tile,
.c3-xgrid-focus,
.c3-ygrid {
  shape-rendering: crispEdges
}

.c3-chart-arc path {
  stroke: #fff
}

.c3-chart-arc text {
  fill: #fff;
  font-size: 13px
}

.c3-grid line {
  stroke: #aaa
}

.c3-grid text {
  fill: #aaa
}

.c3-xgrid,
.c3-ygrid {
  stroke-dasharray: 3 3
}

.c3-text.c3-empty {
  fill: gray;
  font-size: 2em
}

.c3-line {
  stroke-width: 1px
}

.c3-circle._expanded_ {
  stroke-width: 1px;
  stroke: #fff
}

.c3-selected-circle {
  fill: #fff;
  stroke-width: 2px
}

.c3-bar {
  stroke-width: 0
}

.c3-bar._expanded_ {
  fill-opacity: .75
}

.c3-target.c3-focused {
  opacity: 1
}

.c3-target.c3-focused path.c3-line,
.c3-target.c3-focused path.c3-step {
  stroke-width: 2px
}

.c3-target.c3-defocused {
  opacity: .3!important
}

.c3-region {
  fill: #4682b4;
  fill-opacity: .1
}

.c3-brush .extent {
  fill-opacity: .1
}

.c3-legend-item {
  font-size: 12px
}

.c3-legend-item-hidden {
  opacity: .15
}

.c3-legend-background {
  opacity: .75;
  fill: #fff;
  stroke: #d3d3d3;
  stroke-width: 1
}

.c3-tooltip-container {
  z-index: 10
}

.c3-tooltip {
  border-collapse: collapse;
  border-spacing: 0;
  background-color: #fff;
  empty-cells: show;
  -webkit-box-shadow: 7px 7px 12px -9px #777;
  -moz-box-shadow: 7px 7px 12px -9px #777;
  box-shadow: 7px 7px 12px -9px #777;
  opacity: .9
}

.c3-tooltip tr {
  border: 1px solid #CCC
}

.c3-tooltip th {
  background-color: #aaa;
  font-size: 14px;
  padding: 2px 5px;
  text-align: left;
  color: #FFF
}

.c3-tooltip td {
  font-size: 13px;
  padding: 3px 6px;
  background-color: #fff;
  border-left: 1px dotted #999
}

.c3-tooltip td>span {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 6px
}

.c3-tooltip td.value {
  text-align: right
}

.c3-area {
  stroke-width: 0;
  opacity: .2
}

.c3-chart-arcs-title {
  dominant-baseline: middle;
  font-size: 1.3em
}

.c3-chart-arcs .c3-chart-arcs-background {
  fill: #e0e0e0;
  stroke: none
}

.c3-chart-arcs .c3-chart-arcs-gauge-unit {
  fill: #000;
  font-size: 16px
}

.c3-chart-arcs .c3-chart-arcs-gauge-max,
.c3-chart-arcs .c3-chart-arcs-gauge-min {
  fill: #777
}

.c3-chart-arc .c3-gauge-value {
  fill: #000
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/c3/0.4.10/c3.min.js"></script>

<body>
  <br><br>
  <div id="c3_chart" style="width: 90%; height: 270px"></div>

它是如何工作的？ 标签总是生成的，但使用display:none css 配置隐藏。所以我的解决方案是始终跟踪顶部图表中的可见刻度数，当它低于某个阈值（例如放大）时，始终显示这些隐藏标签 (display:block)。

警告

• 当您为某些类名更新 c3 和 d3 时，此函数可能不起作用，或者对象的层次结构可能会发生变化，因此需要更新函数中的逻辑。至少我保留了纯 js 函数，因此不会有影响它的 3rd 方版本更改的问题。