I am working on a project and we are using a chart created with chart js. I want to give the legend a background color (the top part thats drawn in the image). After a lot of searching on the internet i stil havent found a solution to my problem so i thought lets try stack overflow. can some one help me Please??>!
the part i want to give a background color
here is part of my code
enter code here
<div>
<canvas id="myChart"></canvas>
</div>
<script>
const labels = [
'January',
'February',
'March',
'April',
'May',
'June',
];
const data = {
labels: labels,
datasets: [{
label: 'My First dataset',
backgroundColor: 'rgb(255, 99, 132)',
borderColor: 'rgb(255, 99, 132)',
data: [0, 10, 5, 2, 20, 30, 45],
}]
};
const config = {
type: 'line',
data: data,
options: {}
};
var myChart = new Chart(
document.getElementById('myChart'),
config
);
</script>
You can use a custom plugin for this:
const plugin = {
id: 'legendBackground',
beforeDraw: (chart, args, opts) => {
const {
chartArea: {
width,
top,
left
},
ctx
} = chart;
ctx.fillStyle = opts.color || 'transparent';
ctx.fillRect(left, 0, width, top)
}
}
const options = {
type: 'line',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
borderColor: 'orange'
}]
},
options: {
plugins: {
legendBackground: {
color: 'pink'
}
}
},
plugins: [plugin]
}
const ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.7.1/chart.js"></script>
</body>
Related
I want to draw a horizontal reference line at a particular value.
The data is of the format:
{
"Close": 15638.8,
"Date": "2022-06-21T10:00:00.000Z",
"High": 15707.25,
"Low": 15419.85,
"Open": 15455.95,
"Volume": 0,
"id": 36
}
This is what I have figured as of now. I am unsure how to use the refLines attribute.
var dataReqdFormat = {
labels: [],
datasets: [{
data: [],
label: "Nifty",
fill: true,
borderColor: (ctx) => {
const data = ctx.chart.data.datasets[ctx.datasetIndex].data;
return data[0] >= data[data.length - 1] ? 'red' : 'green'
}
}]
};
Any help is appreciated.
You can use the annotation plugin for this:
var options = {
type: 'line',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
borderColor: 'pink'
}]
},
options: {
plugins: {
annotation: {
annotations: {
line: {
type: 'line',
yMin: 16,
yMax: 16,
borderWidth: 2,
borderColor: 'red'
}
}
}
}
}
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.8.0/chart.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/chartjs-plugin-annotation/1.4.0/chartjs-plugin-annotation.js"></script>
</body>
I need the Holiday tooltip to be grouped, that is to say, pressing a tooltip stops seeing all the Holidays. In this way, not having the "Holiday" tooltip repeated twice and showing / hiding with a single tooltip
Is it possible with chart js?
Actual:
Expected:
a single tooltip handling the "Holiday" datasets
Actual code:
var options = {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple"],
datasets: [
{
label: 'HOLIDAY',
data: [10, 10,10,10,10],
borderWidth: 1,
backgroundColor: "red",
stack: 1
},
{
label: 'HOLIDAY',
data: [10, 10,10,10,10],
borderWidth: 1,
backgroundColor: "red",
stack: 2
},
{
label: 'IN OFFICE',
data: [7, 11, 5, 8, 3],
borderWidth: 1,
backgroundColor: "blue",
stack:1
},
{
label: 'HOME OFFICE',
data: [7, 11, 5, 8, 3],
borderWidth: 1,
backgroundColor: "yellow",
stack:2
}
]
},
options: {
indexAxis: 'y',
// Elements options apply to all of the options unless overridden in a dataset
// In this case, we are setting the border of each horizontal bar to be 2px wide
elements: {
bar: {
borderWidth: 2,
}
},
}
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="400" height="100"></canvas>
<script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
</body>
Am trying to create bar graph with multiple plots using chartjs and the graph is generated successfully but one of the legend is not showing correctly.
Am using Chartjs 2.9.3 version.
One of the bar legendary is showing as circle instead of rectangle box. Kindly let me know if any workaround to get the correct legendary.
Bar graph show circle in the legendary
var ctx = document.getElementById('myChart');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
datasets: [
{
label: 'Label1',
data: [3,4],
type: 'scatter',
backgroundColor: 'red',
pointStyle:'circle',
pointRadius:5
},
{
label: 'Label2',
data: [1,2],
type: 'scatter',
backgroundColor: 'blue',
pointStyle:'triangle',
pointRadius:5
},
{
backgroundColor: 'grey',
label: 'Label3',
data: [1,2],
borderWidth: 1,
type: 'bar'
}
]
},
options: {
responsive:false,
legend: {
labels : {
usePointStyle: true
}
},
title: {
display: true
},
scales: {
xAxes: [{
gridLines: {
display: false
}
}],
yAxes: [{
ticks: {
beginAtZero: true
},
scaleLabel: {
display: true,
labelString: '$/MWh'
}
}]
}
}
});
If the usePointstyle flag is set in the legend it defaults to the circle. In V2 this is not configurable for bar charts so you have 2 options
You can switch to a html legend and style that. Or you can update to chart.js version 3 where you can configure it for bar charts:
var options = {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: 'yellow'
},
{
label: '# of Points',
data: [7, 11, 5, 8, 3, 7],
backgroundColor: 'pink',
pointStyle: 'rect'
}
]
},
options: {
plugins: {
legend: {
labels: {
usePointStyle: true
}
}
}
}
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.5.0/chart.js"></script>
</body>
Space between column in chart js
There's the screen of my output and what i want to do
enter image description here
Anyone can help please ?
You can achieve this by setting the barPercentage property
Example:
var options = {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
borderWidth: 1,
backgroundColor: 'blue',
barPercentage: 0.3
},
{
label: '# of Points',
data: [7, 11, 5, 8, 3, 7],
borderWidth: 1,
backgroundColor: 'red',
barPercentage: 0.3
}
]
},
options: {
scales: {
y: {
stacked: true
},
x: {
stacked: true
}
}
}
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.3.2/chart.js"></script>
</body>
Now i have something like this but i need to add space between each column
My charts works well on the same page but when I put on different pages, only the first one works fine.
ex:
Page1.html
<div class="wrapper">
<canvas id="pieChart" width="200px" height="200px"></canvas>
</div>
Page2.html
<div class="wrapper">
<canvas id="lineChart" width="200px" height="200px"></canvas>
</div>
JS
//page1.html
//piechart
var pieVar = {
type: 'pie',
data: {
labels: ["Yes", "No"],
datasets: [
{
data: [60, 40],
backgroundColor: [
"#FF6384",
"#36A2EB"
],
hoverBackgroundColor: [
"#FF6384",
"#36A2EB"
]
}
]
},
options: {
scales: {
xAxes: [{
display: true
}]
}
}
}
//page2.html
//line chart
var lineVar = {
type: 'line',
data: {
labels: ["January", "February", "March", "April", "May", "June", "July"],
datasets: [
{
label: "My First dataset",
fill: true,
lineTension: 0.2,
backgroundColor: "rgba(75,192,192,0.4)",
borderColor: "rgba(75,192,192,1)",
borderCapStyle: 'butt',
borderDash: [],
borderDashOffset: 0.0,
borderJoinStyle: 'miter',
pointBorderColor: "rgba(75,192,192,1)",
pointBackgroundColor: "#fff",
pointBorderWidth: 1,
pointHoverRadius: 10,
pointHoverBackgroundColor: "rgba(255,0,0,1)",
pointHoverBorderColor: "rgba(255,0,0,1)",
pointHoverBorderWidth: 2,
pointRadius: 1,
pointHitRadius: 10,
data: [65, 59, 80, 81, 56, 55, 40],
spanGaps: false,
}
]
},
options: {
scales: {
xAxes: [{
display: true
}]
}
}
}
window.onload = function(){
//piechart
var pieCtx = document.getElementById("pieChart");
var myPieChart = new Chart(pieCtx, pieVar);
//linechart
var lineCtx = document.getElementById("lineChart");
var myLineChart = new Chart(lineCtx, lineVar);
};
In this codepen works fine because it's the same page..
CODEPEN
It sounds like you're loading the same JavaScript file (which contains the configurations for both of your charts) in both of your pages. The problem is since you're using a single JavaScript file with two chart definitions, the chart you try to create that doesn't exist in the html is throwing an error because you are passing in an empty context.
window.onload = function(){
//piechart (this will be null on page2.html)
var pieCtx = document.getElementById("pieChart");
// You are passing in a null pieCtx on page2.html because there is no element with an id = "pieChart"
var myPieChart = new Chart(pieCtx, pieVar);
//linechart (this will be null on page1.html)
var lineCtx = document.getElementById("lineChart");
// You are passing in a null lineCtx on page1.html because there is no element with an id = "lineChart"
var myLineChart = new Chart(lineCtx, lineVar);
};
You should either split your JavaScript file into two files so that the first page only includes the definition for the first chart and the second page only includes the definition for the second chart. Or, add some conditions to prevent trying to create the empty chart (like this).
window.onload = function(){
//piechart (this will be null on page2.html)
var pieCtx = document.getElementById("pieChart");
if (pieChart) {
var myPieChart = new Chart(pieCtx, pieVar);
}
//linechart (this will be null on page1.html)
var lineCtx = document.getElementById("lineChart");
if (lineChart) {
var myLineChart = new Chart(lineCtx, lineVar);
}
};