How do I change the color of each bar in Recharts?

Question

I have a bar graph on one of my React pages. It gets data from props that are passed on from another page. I have a bar graph showing three different pieces of data. One shows, "Correct", the other shows, "Incorrect", and the last shows, "Total". I would like to have the color of each bar be different. I've tried using the Cell feature but couldn't get it to work. I also tried changing the name of each piece of data but no luck. Unfortunately, there's not a lot of documentation out there for Recharts. Anybody have any ideas?

import React from 'react';
import {
    ResponsiveContainer, BarChart, Bar, Cell, XAxis, YAxis, CartesianGrid, Tooltip, Legend,
} from 'recharts';

export default class GameChart extends React.Component {
    constructor(props) {
        super(props);

        this.state = {
            axes: [
                { primary: true, type: 'ordinal', position: 'left' },
                { position: 'bottom', type: 'linear', stacked: true }
            ],
            series: {
                type: 'bar'
            },
            chartData: [
                {
                    name: 'Correct',
                    total: 0,
                },
                {
                    name: 'Incorrect',
                    total: 0,
                },
                {
                    name: 'Total',
                    total: 0,
                },
            ],
            chartLayout: {
                title: 'Math Game Results',
                yaxis: {
                    showticklabels: false
                },
            }
        }
    }

    componentDidUpdate(prevProps) {
        if (prevProps.chartData.totalCounter !== this.state.chartData[2].total) {
            let tempState = this.state;
            tempState.chartData = [
                {
                    name: 'Correct',
                    total: this.props.chartData.correctCounter,
                },
                {
                    name: 'Incorrect',
                    total: this.props.chartData.incorrectCounter,
                },
                {
                    name: 'Total',
                    total: this.props.chartData.totalCounter,
                },
            ];
            this.setState(tempState);
        }
    }

    render () {
        return (
            <div>
                {
                    (this.state.chartData[2].total > 0) ?
                        (<ResponsiveContainer width="95%" height={225}>
                            <BarChart
                                data={this.state.chartData.slice()}
                                layout="vertical" barCategoryGap={5}
                                margin={{top: 5, right: 30, left: 20, bottom: 5,}}
                            >
                                <XAxis
                                    type="number"
                                    stroke="#000000"
                                />
                                <YAxis
                                    type="category"
                                    stroke="#000000"
                                    dataKey="name"
                                />
                                <Tooltip
                                    wrapperStyle={{ width: 100, backgroundColor: '#ccc' }}
                                    formatter={function(name) {return `${name}`}}
                                />
                                <Bar
                                    dataKey="total"
                                    fill="#00a0fc"
                                    stroke="#000000"
                                    strokeWidth={1}
                                />
                            </BarChart>
                        </ResponsiveContainer>
                        ):
                        (null)
                }
            </div>
        );
    }
}

Here's a picture of the current setup. As you can see, each bar has the same color.

Answer 1

Ok, thanks to @c0m1t I got it working. All I had to do was make a list of colors above the state class!

import React from 'react';
import {
    BarChart, Bar, XAxis, Cell, YAxis, Tooltip, ResponsiveContainer,
} from 'recharts';

const barColors = ["#1f77b4", "#ff7f0e", "#2ca02c"]

export default class Example extends React.Component {
    constructor(props) {
        super(props);

        this.state = {
            chartData: [
                {
                    name: "Correct",
                    total: this.props.chartData.correctCounter
                },
                {
                    name: "Incorrect",
                    total: this.props.chartData.incorrectCounter
                },
                {
                    name: "Total",
                    total: this.props.chartData.totalCounter
                }
            ]
        }
    }

    render() {
        return (
            <ResponsiveContainer width="95%" height={450}>
                <BarChart
                    data={this.state.chartData.slice()}
                    margin={{ top: 20, right: 20, left: 20, bottom: 5, }}
                    data={this.state.chartData}
                >
                <XAxis
                    dataKey="name"
                    stroke="#000000"
                />
                <YAxis
                    stroke="#000000"
                />
                <Tooltip
                    wrapperStyle={{ width: 100, backgroundColor: '#ccc' }}
                    formatter={function(total) {return `${total}`}}
                />
                <Bar
                    dataKey="total"
                    fill="#00a0fc"
                    stroke="#000000"
                    strokeWidth={1}
                >
                    {
                        this.state.chartData.map((entry, index) => (
                            <Cell key={`cell-${index}`} fill={barColors[index % 20]} />
                        ))
                    }
                </Bar>
                </BarChart>
            </ResponsiveContainer>
        );
    }
}

Now each bar has a different color.

Answer 2

You can add the fill color to the chartData directly using the fill key:

[
    {
        name: 'Correct',
        total: 0,
        fill: '#1f77b4',
    },
    {
        name: 'Incorrect',
        total: 0,
        fill: '#ff7f0e',
    },
    {
        name: 'Total',
        total: 0,
        fill: '#2ca02c',
    },
]