chartIndex

Overview

chartIndex is an interactive component used to view the relative trends of line charts compared to a specific time point.

import { Chart } from '@antv/g2';

const chart = new Chart({
  container: 'container',
  paddingLeft: 50,
});

chart.options({
  type: 'line',
  data: {
    type: 'fetch',
    value: 'https://assets.antv.antgroup.com/g2/indices.json',
  },
  encode: {
    x: (d) => new Date(d.Date),
    y: 'Close',
    color: 'Symbol',
    key: 'Symbol',
    title: (d) => d.Date.toLocaleString(),
  },
  axis: {
    y: {
      title: '↑ Change in price (%)',
      labelAutoRotate: false,
    },
  },
  scale: {
    y: {
      type: 'log',
    },
  },
  label: {
    text: 'Symbol',
    selector: 'last',
    style: {
      fontSize: 10,
    },
  },
  interaction: {
    chartIndex: {
      ruleStroke: '#aaa',
      labelDx: 5,
      labelTextAlign: 'center',
      labelStroke: '#fff',
      labelLineWidth: 5,
      labelFormatter: (d) => `${d.toLocaleDateString()}`,
    },
  },
});

chart.render();

Usage

chartIndex is configured through configuration options:

({
  type: 'line',
  interaction: {
    chartIndex: {},
  },
});

Configuration Level

Interaction can be configured at the Mark level:

({
  type: 'line',
  interaction: { chartIndex: {} },
});

It can also be configured at the View level. Interactions declared on the view will be passed to marks declared in children. If the mark has declared the corresponding interaction, they will be merged; otherwise, it won’t be affected.

({
  type: 'line',
  interaction: { chartIndex: {} },
});

Configuration Options

Property	Description	Type	Default
ruleStroke	Color of the indicator line	string	`black`
ruleLineWidth	Width of the indicator line	number	`1`
ruleLineDash	Dash configuration. First value is dash length, second is gap length. Setting ruleLineDash to [0,0] means no stroke.	`[number,number]`
ruleStrokeOpacity	Opacity of the indicator line	number
ruleOpacity	Overall opacity	number
ruleShadowColor	Indicator line shadow color	string
ruleShadowBlur	Indicator line Gaussian blur coefficient	number
ruleShadowOffsetX	Horizontal distance of shadow from indicator line	number
ruleShadowOffsetY	Vertical distance of shadow from indicator line	number
labelFontSize	Text size	number
labelFontFamily	Text font	string
labelFontWeight	Font weight	number
labelLineHeight	Text line height	number
labelTextAlign	Set the current alignment of text content	`center` \| `end` \| `left` \| `right` \| `start`
labelTextBaseline	Set the current text baseline used when drawing text	`top` \| `middle` \| `bottom` \| `alphabetic` \| `hanging`
labelFill	Text fill color	string
labelFillOpacity	Text fill opacity	number
labelStroke	Text stroke	string
labelLineWidth	Text stroke width	number
labelLineDash	Stroke dash configuration. First value is dash length, second is gap length. Setting labelLineDash to [0,0] means no stroke.	`[number,number]`
labelStrokeOpacity	Stroke opacity	number
labelOpacity	Text overall opacity	number
labelShadowColor	Text shadow color	string
labelShadowBlur	Text shadow Gaussian blur coefficient	number
labelShadowOffsetX	Set horizontal distance of shadow from text	number
labelShadowOffsetY	Set vertical distance of shadow from text	number
labelDx	Text offset in x direction	number
labelDy	Text offset in y direction	number
labelFormatter	Format date	`FormatterFunction`

Examples

Indicator Line and Text

import { Chart } from '@antv/g2';

const chart = new Chart({
  container: 'container',
});
chart.options({
  type: 'line',
  autoFit: true,
  data: {
    type: 'fetch',
    value: 'https://assets.antv.antgroup.com/g2/indices.json',
  },
  encode: {
    x: (d) => new Date(d.Date),
    y: 'Close',
    color: 'Symbol',
    key: 'Symbol',
    title: (d) => d.Date.toLocaleString(),
  },
  axis: {
    y: {
      title: '↑ Change in price (%)',
      labelAutoRotate: false,
    },
  },
  scale: {
    y: {
      type: 'log',
    },
  },
  label: {
    text: 'Symbol',
    selector: 'last',
    style: {
      fontSize: 10,
    },
  },
  interaction: {
    tooltip: {
      crosshairs: false, // Disable auxiliary lines
    },
    chartIndex: {
      ruleStroke: 'pink',
      ruleLineWidth: 8,
      ruleLineDash: [4, 8],
      ruleShadowColor: 'green',
      ruleShadowBlur: 5,
      ruleShadowOffsetX: 5,
      ruleShadowOffsetY: 5,
      ruleOpacity: 0.9,
      labelDy: 30,
      labelFontSize: 20,
      labelTextAlign: 'center',
      labelFill: 'red',
      labelStroke: 'yellow',
      labelLineWidth: 2,
      labelFormatter: (d) => `${d.toLocaleDateString()}`,
    },
  },
});

chart.render();