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Error in fill Gradient Color in Line Chart.js

I try to Fill gradient Color in my Line chart but there was some error restricted me from using canvas.
In Code Below there are 3 function: Options contain options of the line chart, Data contain data(i have error in this function), LineChart call and return line chart
import React from "react";
import {
Chart as ChartJS,
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend,
Filler
} from "chart.js";
import { Line } from "react-chartjs-2";
ChartJS.register(
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend,
Filler
);
export const options = {
responsive: true,
maintainAspectRatio: true,
aspectRatio: 1,
plugins: {
legend: {
position: "top",
display: false,
},
title: {
display: true,
text: "Calories Friend Ranking",
},
},
backgroundColor: "#fff",
borderColor: "#fff",
};
export const data = (canvas) => {
const ctx = canvas.getContext("2d");
const gradient = ctx.createLinearGradient(0, 0, 0, 400);
gradient.addColorStop(0, 'rgba(250, 61, 0 ,1)');
gradient.addColorStop(1, 'rgba(250, 61, 0 ,0)');
return {
labels: ["0","cuong","hien"],
datasets: [
{
backgroundColor : gradient,
borderColor : "rgba(250, 61, 0, 1)",
tension: 0.4,
fill: 'start',
data : [0,500,2000]
}
]
}
}
export default function LineChart(props) {
let { RankData } = props;
var NameLabels = ["0"]
var CaloriesDatas = [0]
for (var i = RankData.length - 1; i >= 0; i--) {
NameLabels.push(RankData[i].displayName)
CaloriesDatas.push(RankData[i].carloriesBurned)
}
//error in data function :"Property 'datasets' is missing in type '(canvas: any) =>.."
return (<Line data={data} options={options} />);
}
I have error in function Data "Here is the error that i met"

Styling background (fill) with ChartJs and React [closed]

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I want to create a Line chart, styled as an Area Chart, in React by using the chartJS library ('react-chartjs-2')
This is what I want to achieve, like background (fill) with some opacity below the line:
Code:
import React from 'react';
import {
Chart as ChartJS,
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend,
} from 'chart.js';
import { Line } from 'react-chartjs-2';
import faker from 'faker';
ChartJS.register(
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend
);
export const options = {
responsive: true,
plugins: {
legend: {
position: 'top' as const,
},
title: {
display: true,
text: 'Chart.js Line Chart',
},
},
};
const labels = ['January', 'February', 'March', 'April', 'May', 'June', 'July'];
export const data = {
labels,
datasets: [
{
label: 'Dataset 1',
data: labels.map(() => faker.datatype.number({ min: -1000, max: 1000 })),
borderColor: 'rgb(255, 99, 132)',
backgroundColor: '#000000',
fill: {
target: 'origin',
above: 'rgb(255, 0, 0)', // Area will be red above the origin
below: '#000000' // And blue below the origin
}
},
{
label: 'Dataset 2',
data: labels.map(() => faker.datatype.number({ min: -1000, max: 1000 })),
borderColor: 'rgb(53, 162, 235)',
backgroundColor: 'rgba(53, 162, 235, 0.5)',
},
],
};
export function App() {
return <Line options={options} data={data} />;
}
How can I achieve this with ChartJS ('react-chartjs-2')?

Yes -- ChartJS/react-chartjs-2 does support this. In order to do this, you need to:
Import/register the chart.js Filler plugin (Mentioned in the docs for Area Charts)
Set the tension of the line (to make the lines curve), and;
Set the fill options for the dataset.
Following these steps this will produce:
For example:
import React from "react";
import { Line } from "react-chartjs-2";
import {
Chart as ChartJS,
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend,
Filler // 1. Import Filler plugin
} from "chart.js";
import faker from "faker";
ChartJS.register(
CategoryScale,
LinearScale,
PointElement,
LineElement,
Title,
Tooltip,
Legend,
Filler // 1. Register Filler plugin
);
export const options = {
responsive: true,
tension: 0.3 // 2. Set the tension (curvature) of the line to your liking. (You may want to lower this a smidge.)
};
const labels = ["January", "February", "March", "April", "May", "June", "July"];
export const data = {
labels,
datasets: [
{
label: "Dataset 1",
data: labels.map(() => faker.datatype.number({ min: 0, max: 500 })),
borderColor: "rgb(255, 99, 132)",
backgroundColor: "rgba(255, 0, 0)",
fill: {
target: "origin", // 3. Set the fill options
above: "rgba(255, 0, 0, 0.3)"
}
},
{
label: "Dataset 2",
data: labels.map(() => faker.datatype.number({ min: 0, max: 500 })),
borderColor: "rgb(53, 162, 235)",
backgroundColor: "rgba(53, 162, 235, 0.3)",
fill: "origin" // 3. Set the fill options
}
]
};
export function App() {
return <Line options={options} data={data} />;
}
Working CodeSanbox: https://codesandbox.io/s/chartjs-area-chart-p1o023?file=/App.tsx:817-846

add a unit to label with chartjs plugin datalabels

I am opening a new question following Rohit's answer on this question Chart.js Show labels on Pie chart
Is it possible to modify the labels with the plugin chartjs datalabels, for exemple add a unit to it?
Thanks for your answer!
EDIT:
Following Ty answer, I tried this:
if(type==='pie'){
GraphOpt['plugins'] = {
datalabels: {
formatter: (item) => {
return item + ' ' + label_unit;
}
}
}
}
else{
GraphOpt['tooltips'] = {
callbacks: {
label: (item) => `${item.yLabel} ${label_unit}`,
}
}
}
but it's still not showing the units on the graph.
Also, I can't get rid of the values showing on bar graphes with the plugin
EDIT2: My graph function
function setChart(Graph, ctx, type, graph_data, labels, title, label_graph, label_unit){
var GraphOpt = {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
},
title: {
display:true,
text: title,
},
tooltips: {},
plugins : {}
}
//graph config
var Graph_config = {
type: type,
data: {
labels: labels,
datasets: [{
label: label_graph,
data: graph_data,
backgroundColor: backgroundColor,
borderColor: backgroundColor,
borderWidth: 1
}]
},
options: GraphOpt,
}
if(type==='pie'){
GraphOpt['plugins'] = {
datalabels: {
formatter: (item) => {
return item + ' ' + label_unit;
}
}
}
}
else{
GraphOpt['tooltips'] = {
callbacks: {
label: (item) => `${item.yLabel} ${label_unit}`,
}
}
}
//create a new graph if graph doesn't exist (init)
console.log(typeof window[Graph])
if(typeof window[Graph] === "undefined") {
window[Graph] = new Chart(ctx, Graph_config);
console.log(typeof window[Graph])
//update if graph exist
}else{
console.log('Graph Update')
//updating with new chart data
window[Graph].config=Graph_config;
window[Graph].title=title;
//redraw the chart
window[Graph].update();
}
}

Yes, have a look at the chartjs-plugin-datalabels documentation. In particular, you want to use the options.plugins.datalabels.formatter option to specify a custom function and append units to every label string.
Here's an example Chart.js config that adds a unit to every data label:
{
type: 'pie',
data: {
datasets: [
{
data: [84, 28, 57, 97],
backgroundColor: [
'rgb(255, 99, 132)',
'rgb(255, 159, 64)',
'rgb(255, 205, 86)',
'rgb(75, 192, 192)',
],
label: 'Dataset 1',
},
],
labels: ['Red', 'Orange', 'Yellow', 'Green'],
},
options: {
plugins: {
datalabels: {
formatter: (val) => {
return val + ' kg';
}
}
}
}
}

ChartJS with React: Only one value showing on time chart

I am creating a cryptocurrency price tracker with React. I am using axios to make API requests and get information about the price history of different cryptocurrencies. This works fine, but when I am creating the chart with ChartJS, the chart only shows one value, even though I have thousands. Anyone know how to fix this? Big thanks in advance.
Here is my code for the chart component:
import Chartjs from "chart.js";
import axios from "axios";
import { historyOptions } from "../../chartConfigs/chartConfigs";
const HistoryChart = ({ coinId }) => {
const [timeLength, setTimeLength] = useState(30);
const chartRef = useRef();
const [timeSeriesData, setTimeSeriesData] = useState([]);
useEffect(() => {
const timeSeriesDataArray = [];
axios.get(`https://api.coingecko.com/api/v3/coins/${coinId}/market_chart?vs_currency=usd&days=${30}`)
.then(response => {
response.data.prices.forEach(element => {
timeSeriesDataArray.push(
{
t: element[0],
y: element[2].toFixed(2)
}
)
})
setTimeSeriesData(timeSeriesDataArray)
})
.catch(error => console.log(error))
}, [coinId, timeLength])
useEffect(() => {
if (chartRef && chartRef.current) {
const chartInstance = new Chartjs(chartRef.current,{
type: 'line',
data: {
datasets: [{
label: "Price",
data: timeSeriesData,
backgroundColor: "rgba(174, 374, 194, 0.5)",
borderColor: "rgba(174, 374, 194, 0.4)",
pointRadius: 0,
borderWidth: 1
}]
},
options: historyOptions
})
}
}, [timeSeriesData])
return (
<div className="history-chart-container">
<canvas ref={chartRef} id="history-chart" width={1200} height={500}></canvas>
</div>
)
}
export default HistoryChart
Here is my code for the chart options (historyOptions):
lineHeighAnnotation: {
always: true,
hover: false,
lineHeight: 1.5
},
animation: {
duration: 2000
},
maintainAspectRatio: false,
responsive: true,
scales: {
xAxes: {
type: "time",
distribution: "linear",
}
}
}```
[1]: https://i.stack.imgur.com/e7g4P.png
[2]: https://i.stack.imgur.com/t4YIa.png

This could be fixed by changing your line chart into a scatter chart.
const chartInstance = new Chartjs(chartRef.current,{
type: 'scatter',
...
To still get the lines drawn between the data points, you need to define the option showLine: true on the dataset.
datasets: [{
label: "Price",
showLine: true,
...
}]
UPDATE
You should also make sure to update the chart when new data is added and the chart already exists. Not knowing much about react.js, you could make chartInstance a global variable and proceed as follows:
if (chartRef && chartRef.current) {
chartInstance = new Chartjs(chartRef.current,{
type: 'line',
...
} else {
chartInstance.update();
}

chart js 2 how to set bar width

I'm using Chart js version: 2.1.4 and I'm not able to limit the bar width. I found two options on stackoverflow
barPercentage: 0.5
or
categorySpacing: 0
but neither of one works with the mentioned version. Is there a way to solve this issue without manually modifying the chart.js core library?
thanks

You were right : The attribute you have to edit is barPercentage.
But maybe the error comes from where you edited the value.
As you can see in the bar chart options :
Name : barPercentage
- Type : Number
- Default : 0.9
- Description : Percent (0-1) of the available width each bar should be within the category percentage. 1.0 will take the whole category width and put the bars right next to each other. Read More
The attribute is actually stored in scales.xAxes ("Options for xAxes" table).
So you just have to edit your chart this way :
var options = {
scales: {
xAxes: [{
barPercentage: 0.4
}]
}
}
Here is a fully working example with a custom width (0.2) for the bar :
var data = {
labels: ["January", "February", "March", "April", "May", "June", "July"],
datasets: [{
label: "My First dataset",
backgroundColor: "rgba(75,192,192,0.4)",
borderColor: "rgba(75,192,192,1)",
data: [65, 59, 75, 81, 56, 55, 40],
}]
};
var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
type: 'bar',
data: data,
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}],
xAxes: [{
// Change here
barPercentage: 0.2
}]
}
}
});
console.log(myChart);
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.1.6/Chart.js"></script>
<canvas id="myChart"></canvas>
Update (Chart.js Version 2.2.0+)
As stated in the Release Version 2.2.0 - Candidate 2 :
Enhancements
Can now manually configure the thickness of a bar in a bar chart. Use a new barThickness option on the correct axis to set the thickness of a bar.
And so on ...

For version 2.8+ (and apparently as far back as 2.2), there are now some excellent controls over the bar thickness, max thickness, etc.
Per the Chart.js documentation, you would set them like so:
{
type: 'bar', // or 'horizontalBar'
data: ...,
options: {
scales: {
xAxes: [{
barThickness: 6, // number (pixels) or 'flex'
maxBarThickness: 8 // number (pixels)
}]
}
}
}

As of v2.7.2 it can be done by:
scales: {
xAxes: [{
maxBarThickness: 100,
}],
}

In case if you are using ng2-chart in an angular project then the bar chart configuration looks Alike this:
npm install ng2-charts chart.js --save
import 'ng2-charts' in your module.
import { ChartsModule } from 'ng2-charts';
Now the bar chart configurations:
barChartOptions: ChartOptions = {
responsive: true,
maintainAspectRatio: false,
legend: {
display: false
},
};
barChartLabels: Label[] = ['2006', '2007', '2008', '2009', '2010', '2011', '2012'];
barChartType: ChartType = 'bar';
barChartLegend = true;
barChartPlugins = [];
barChartData: ChartDataSets[] = [
{
barThickness: 16,
barPercentage: 0.5,
data: [65, 59, 80],
label: 'Growth'
},
{
barThickness: 16,
barPercentage: 0.5,
data: [28, 48, 40],
label: 'Net'
}
];
barChartColors: Color[] = [
{ backgroundColor: '#24d2b5' },
{ backgroundColor: '#20aee3' },
];
Now the HTML part:
<div class="bar-chart-wrapper">
<canvas baseChart [datasets]="barChartData" [colors]="barChartColors"
[labels]="barChartLabels"
[options]="barChartOptions" [plugins]="barChartPlugins" [legend]="barChartLegend"
[chartType]="barChartType">
</canvas>
</div>
You can control the height of your chart container
.bar-chart-wrapper {
height: 310px;
}

barThickness and maxBarThickness (previously in ChartOptions[]) are now a part of ChartDataSets[].

As per above answer
Here is complete Bar chart graph using react chartjs2.
import React from 'react';
import {
Chart as ChartJS,
CategoryScale,
LinearScale,
BarElement,
Title,
Tooltip,
Legend,
} from 'chart.js';
import { Bar } from 'react-chartjs-2';
ChartJS.register(
CategoryScale,
LinearScale,
BarElement,
Title,
Tooltip,
Legend
);
export const options = {
responsive: true,
plugins: {
legend: {
position: 'top', // lable position left/right/top/bottom
labels: {
boxWidth: 0, // lable box size
}
},
},
elements: {
point: {
radius: 1
}
},
scales: {
x: {
display: false, // show/ hide x-axis
grid: {
display: false // show/hide grid line in x-axis
},
},
y: {
display: false, // same as x-axis
grid: {
display: false
}
}
}
};
const labels = ['January', 'February', 'March', 'April', 'May', 'June', 'July'];
export const data = {
labels,
datasets: [
{
label: 'datasets', // label text
data: [100, 300, 500, 700],
backgroundColor: '#7b62ff', // bar / column color
barThickness: 6, // <<<<<<<<<<<< bar / column size
},
],
};
export default function ResumesGraph() {
return (
<div>
<Bar
data={data}
options={options}
width={'500px'}
height={'180px'}
/>
</div>
);
}

Try this
import {Chart} from "chart.js"
Chart.defaults.datasets.bar.maxBarThickness = 73;
//also try barPercentage

For those who are interested, i made a quick fork based on 3.9 branch to manage dynamic width :
https://github.com/stephanebouget/Chart.js/tree/3.9
For example :
Live demo
https://codepen.io/stephanebouget/pen/PoerxPP
var data = {
datasets: [{
label: 'Dataset #1',
backgroundColor: 'rgba(255,99,132,0.2)',
borderColor: 'rgba(255,99,132,1)',
borderWidth: 1,
hoverBackgroundColor: 'rgba(255,99,132,0.4)',
hoverBorderColor: 'rgba(255,99,132,1)',
data: [65, 59, 20, 81, 56, 55, 40],
setPercentage: [10, 2, 20, 40, 4, 6, 18], // Here is the magic !!!
}],
};