Totals for stacked bars

[ghost]

Is your feature request related to a problem? Please describe.
I don't know if there is a way to show the totals of stacked bars as asked in

Describe the solution you'd like
Being able to show the total of the portions of the stacked bar over the bars or as the number of the last segment.

Additional context
I opened this issue, because there is a closed similar issue (#951) where the last message says: "Closing this issue after a prolonged period of inactivity. If this issue is still present in the latest release, please create a new issue with up-to-date information. Thank you!"

I personally need a solution to this in a project I'm working and I suspect other people are looking for one too.

[ghost]

I mention @Mulli and @timothyarmes who asked for this feature in the other issue (#951).

[Mulli]

@damianocasula I am still waiting for a solution... Thanks for re-opening

[tkonopka]

Hi @damianocasula, hi @Mulli. Do you mean something like this?

https://codesandbox.io/s/hopeful-mcclintock-44m0w8?file=/src/App.js

This implementation uses a custom layer. Note the sandbox only works for vertical bar plots, but hopefully you can customize it for your needs.

[Mulli]

Hi Tomasz Thanks for taking the time to show the example I shall give it a try Best Mulli Bahr +972-50-9262025 https://site2goal.co.il ‫בתאריך שבת, 28 במאי 2022 ב-19:47 מאת ‪Tomasz Konopka‬‏ <‪ ***@***.***‬‏>:‬

…

Hi @damianocasula <https://github.com/damianocasula>, hi @Mulli <https://github.com/Mulli>. Do you mean something like this? [image: 2022-05-28-bar-totals] <https://user-images.githubusercontent.com/7260190/170834387-752b8ce7-07e8-45c0-bf44-d343444d2b7e.png> https://codesandbox.io/s/hopeful-mcclintock-44m0w8?file=/src/App.js This implementation uses a custom layer. Note the sandbox only works for vertical bar plots, but hopefully you can customize it for your needs. — Reply to this email directly, view it on GitHub <#2020 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAF25U7EFW6NPEMR2ERKME3VMJE3XANCNFSM5XENTCEA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[stale]

This issue has been automatically marked as stale. If this issue is still affecting you, please leave any comment (for example, "bump"), and we'll keep it open. We are sorry that we haven't been able to prioritize it yet. If you have any new additional information, please include it with your comment!

[stale]

Closing this issue after a prolonged period of inactivity. If this issue is still present in the latest release, please create a new issue with up-to-date information. Thank you!

[ChuckJonas]

Converted this solution to typescript (and did some very slight refactoring).

const BarTotalsLayer: BarLayer<{ value: number }> = ({
  bars,
  xScale,
  yScale,
}) => {
  const labelOffset = 10;
  const labelFontSize = 12;
  if (bars.length === 0) return null;
  // compute totals for each index/bar

  const totals = bars.reduce<Record<number, number>>((acc, bar) => {
    console.log(bar.data.indexValue);
    const indexValue = bar.data.indexValue;
    if (!(indexValue in acc)) {
      acc[indexValue] = 0;
    }
    if (!bar.data.hidden) {
      acc[indexValue] += bar.data.value;
    }
    return acc;
  }, {});

  const bandwidth = bars[0]?.width;
  // place text elements above the bars
  const labels = (Object.keys(totals) as any as number[]).map((indexValue) => {
    const x = xScale(indexValue) + bandwidth / 2;
    const y = yScale(totals[indexValue]) - labelOffset;
    return (
      <text
        key={'total.' + indexValue}
        x={x}
        y={y}
        textAnchor={'middle'}
        fontWeight={'bold'}
        fontSize={labelFontSize}
      >
        {totals[indexValue]}
      </text>
    );
  });
  return <>{labels}</>;
};

Note: to get the types to work, you also need to install @types/d3-scale as indicated in #2173

[joaopedromatias]

@tkonopka thank you so muchhhh man 🚀

[elijahnikov]

For anyone having trouble doing this for the <ResponsiveBarCanvas/> component like I did trying the above solutions, you need to draw directly onto the canvas using the context provided by Nivo. This is what worked for me:

Version of Nivo I used:

"@nivo/bar": "^0.83.0",
"@nivo/core": "^0.83.0",

Import the types from @nivo/bar

import {
  ResponsiveBarCanvas,
  BarCanvasCustomLayerProps,
  BarDatum,
} from '@nivo/bar'

Add the component to the layers prop

layers={['axes', 'bars', BarTotalsLayer]}

const BarTotalsLayer = (
  context: CanvasRenderingContext2D,
  props: BarCanvasCustomLayerProps<BarDatum>
) => {
  const { bars, xScale, yScale } = props
  const labelOffset = 5
  const labelFontSize = 12
  if (bars.length === 0) return null

  const totals = bars.reduce<Record<number, number>>((acc, bar) => {
    const indexValue = bar.data.indexValue
    if (!(indexValue in acc)) {
      acc[indexValue as keyof typeof acc] = 0
    }
    if (!bar.data.hidden) {
      acc[indexValue as keyof typeof acc] += bar.data.value!
    }
    return acc
  }, {})

  const bandwidth = bars[0]?.width

  return (Object.keys(totals) as any as number[]).forEach((indexValue) => {
    const x = xScale(indexValue) + bandwidth / 2
    const y = yScale(totals[indexValue]) - labelOffset

    context.font = `600 ${labelFontSize}px 'IBM Plex Sans', sans-serif`
    context.fillStyle = '#575756'
    context.textAlign = 'center'
    context.fillText(`${totals[indexValue]}`, x, y - labelOffset)
  })
}

Of course adjust the styling how you desire

[plouc]

Implemented in #2525 thanks to @joaopedromatias.