I am using below code to populate slice values in a pie chart using JS and it's correctly working but
I am observing another problem as these values are getting populated only once and when I reload the charts it's getting disappeared. Now let's say if I close the browser and open again or change the browser it will show values again. But after doing multiple force refresh Ctrl+F5 then also it's not showing the values. Could you please help?
Please note I am having more than 3 pie charts on the same page with a different id.
var canvas = document.getElementById('myChart');
new Chart(canvas, {
type: 'pie',
data: {
labels: ['January', 'February', 'March'],
datasets: [{
data: [50445, 33655, 15900],
backgroundColor: ['#FF6384', '#36A2EB','#FFCE56']
}]
},
options: {
responsive: true,
maintainAspectRatio: true,
plugins: {
labels: {
render: 'percentage',
fontColor: ['green', 'white', 'red'],
precision: 2
}
},
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<script src="https://cdn.jsdelivr.net/gh/emn178/chartjs-plugin-labels/src/chartjs-plugin-labels.js"></script>
<canvas id="myChart"></canvas>
Related
I am using chart.js for my project. As you can see in the following code, chart.js uses different minimum and maximum values for y-axis for line and bar graphs for same data. In the given code, 1100-1700 is the value range for line graph whereas 0-2000 is the value range used for bar graph.
I like to make same minimum and maximum values for both line and bar graphs. One option is to find minimum, maximum and step-size values my own and use the properties min, max and ticks.stepSize under scales. But finding minimum, maximum and step-size for a given data data is a serious task.
For my requirement, default minimum ,maximum and stepSize used by chart.js for line graph is fine and I would like to use the same values for bar graph also.
I could first render line graph, get these values from this graph (like scales.y.min) and then use it for bar graph, which is perfectly working
Is there a way I could get the default min, max, stepSize values used by chart.js for line graph before actually drawing the graph? Any answers or pointers are really appreciated. Thanks
var chart1 = new Chart(document.getElementById('chart1'),
{
type: 'line',
data:
{
labels: ['a','b','c'],
datasets:
[
{
label: 'A',
data: [1212,1122, 1188, 1617, 1116],
borderColor: 'green',
}
]
}
});
var chart2 = new Chart(document.getElementById('chart2'),
{
type: 'bar',
data:
{
labels: ['a','b','c'],
datasets:
[
{
label: 'A',
data: [1212,1122, 1188, 1617, 1116],
backgroundColor: 'green',
}
]
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.9.1/chart.min.js"></script>
<div style="width:300px;height:200px"><canvas id="chart1"></canvas></div>
<div style="width:300px;height:200px"><canvas id="chart2"></canvas></div>
The first thing you could do is to set beginAtZero to false to Y axis of bar chart because is set to true by default:
https://github.com/chartjs/Chart.js/blob/v3.9.1/src/controllers/controller.bar.js#L636-L650
Then you can set the same scale config to both charts.
options: { // options of charts
scales: {
y: {
beginAtZero: false,
}
}
}
var chart1 = new Chart(document.getElementById('myChart1'),
{
type: 'line',
data:
{
labels: ['a','b','c'],
datasets:
[
{
label: 'A',
data: [1212,1122, 1188, 1617, 1116],
borderColor: 'green',
}
]
},
options: {
scales: {
y: {
beginAtZero: false,
}
}
}
});
var chart2 = new Chart(document.getElementById('myChart2'),
{
type: 'bar',
data:
{
labels: ['a','b','c'],
datasets:
[
{
label: 'A',
data: [1212,1122, 1188, 1617, 1116],
backgroundColor: 'green',
}
]
},
options: {
scales: {
y: {
beginAtZero: false,
}
}
}
});
.myChartDiv {
max-width: 300px;
max-height: 200px;
}
<script src="https://cdn.jsdelivr.net/npm/chart.js#3.9.1/dist/chart.min.js"></script>
<html>
<body>
<div class="myChartDiv">
<canvas id="myChart1" width="300" height="200"/>
</div>
<div class="myChartDiv">
<canvas id="myChart2" width="300" height="200"/>
</div>
</body>
</html>
I am using Chart.js v3.4 with Vue3. Here is my chart:
I am wondering if there is a way to remove the tick marks that go past the axis of the chart (pointing to the axis labels) so that the shape is a solid rectangle with labels.
Note: I am already using the drawBorder: false option for the y-axis.
Secondly I want to make it so there are exactly 5 grid lines on the y-axis to keep 4 rows of boxes on the chart at all times. I'm using dynamic data and ranges so the amount of boxes changes depending on the data. (You can see a new box just barely started at the bottom of the chart, I don't want that to be showing). The way I determine the min and max of the chart is by taking the min/max of the data array and subtracting/adding 2 to them.
You can make use of the drawTicks and count propertys to achieve what your want.
Live example:
var options = {
type: 'line',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3]
}]
},
options: {
scales: {
y: {
ticks: {
count: 5,
padding: 10
},
grid: {
drawTicks: false
}
},
x: {
ticks: {
padding: 10
},
grid: {
drawTicks: false
}
}
}
}
}
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/3.4.0/chart.js"></script>
</body>
For some reason, the legend on this doughnut chart created with chart.js is not moving to the right. Even tried adding the rule to chart creation itself instead of putting it in the variable
EDIT
With further inspection, it appears any options that are set to the legend do not appear to be working.
const mobileData = {
labels: ["Desktop", "Tablet", "Phons"],
datasets: [{
label: '# of Users',
data: [2000, 550, 500],
borderWidth: 0,
backgroundColor: [
'#7477BF',
'#78CF82',
'#51B6C8'
]
}]
};
const mobileOptions = {
legend: {
position: 'right',
labels: {
boxwidth: 20,
fontStyle: 'bold'
}
}
}
let mobileChart = new Chart(mobileCanvas, {
type: 'doughnut',
data: mobileData,
options: mobileOptions
});
Here's a fiddle to the project minus images.
https://jsfiddle.net/5j2ucpv6/3/
You are using the new V3 version of the lib instead of V2
So please read the migration guide from chart.js (https://www.chartjs.org/docs/latest/getting-started/v3-migration.html)
The legend options have been moved to the plugin section like this
options: {
plugins: {
legend: {
position: 'right'
}
}
}
I have several charts on a production tracking page, I'd like to avoid this effect that makes tracking inconsistent at first glance. Is there any option in chart.js for that ? If not, what is the best way to resolve this problem ?
I tried the option "bar percentage : 0.2", but the problem is it resolves only the width, not the height, and it causes another problem where there are several datas (it's ugly) :
To achieve this you will need to know the max value of your first chart. If you know this you can set the the suggestedMax value in the ticks options for the yAxes to that value.
var options = {
type: 'bar',
data: {
labels: ["Red"],
datasets: [{
label: '# of Votes',
data: [2],
borderWidth: 1,
}]
},
options: {
scales: {
yAxes: [{
ticks: {
suggestedMax: 25
}
}]
}
}
}
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/2.9.4/Chart.js" integrity="sha512-hZf9Qhp3rlDJBvAKvmiG+goaaKRZA6LKUO35oK6EsM0/kjPK32Yw7URqrq3Q+Nvbbt8Usss+IekL7CRn83dYmw==" crossorigin="anonymous"></script>
</body>
I am having an scenario, where I need to show the slice value inside of the slice in pie chart. I am having more than 1 pie charts on my webpage. Below code is perfectly working but only for 1st Pie Chart and for others its throwing error as below, could you please help me to sort this out?
Error:: unCaught TypeError: cannot read the property 'data' of undefined.
Code::
options:{
animation:{
onComplete:function(){
var ctx = this.chart.ctx;
var dataset_obj = this.data.datasets;
for (var i=0;i<dataset_obj.length; i++){
var meta_obj = dataset_obj[i]._meta[i].data;
for (var j=0; j<meta_obj.length; j++){
var model =meta_obj[j]._model;
start_angle= model.startAngle;
end_angle = model.endAngle;
mid_angle =start_angle + ( end_angle -start_angle)/2;
mid_radius = model.innerRadius + (model.outerRadius -model.innerRadius)/2;
var x =mid_radius*math.cos(mid_angle);
var y = mid_radius*math.cos(mid_angle);
ctx.fillstyle='#fff';
if (dataset_obj[i].data[j] != 0 && meta_obj[j].hidden != true){
ctx.fillText(dataset_obj[i].data[j], model.x+x, model.y+y);
}
}
}
}
}
}
This answers the issue contained in the question's title:
How to show slice value inside of slice in pie chart using chart.js
The code snippet below show how to display the values inside the slices with the use of chartjs-plugin-labels. The code of the samples was extracted from the chartjs-plugin-labels demo page.
var canvas = document.getElementById('myChart');
new Chart(canvas, {
type: 'pie',
data: {
labels: ['January', 'February', 'March'],
datasets: [{
data: [50445, 33655, 15900],
backgroundColor: ['#FF6384', '#36A2EB','#FFCE56']
}]
},
options: {
responsive: true,
maintainAspectRatio: true,
plugins: {
labels: {
render: 'value',
fontColor: ['green', 'white', 'red']
}
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<script src="https://cdn.jsdelivr.net/gh/emn178/chartjs-plugin-labels/src/chartjs-plugin-labels.js"></script>
<canvas id="myChart"></canvas>
If you want to display the percentage of each slice, you can do the following:
var canvas = document.getElementById('myChart');
new Chart(canvas, {
type: 'pie',
data: {
labels: ['January', 'February', 'March'],
datasets: [{
data: [50445, 33655, 15900],
backgroundColor: ['#FF6384', '#36A2EB','#FFCE56']
}]
},
options: {
responsive: true,
maintainAspectRatio: true,
plugins: {
labels: {
render: 'percentage',
fontColor: ['green', 'white', 'red'],
precision: 2
}
},
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<script src="https://cdn.jsdelivr.net/gh/emn178/chartjs-plugin-labels/src/chartjs-plugin-labels.js"></script>
<canvas id="myChart"></canvas>