I am trying to create Chart using Chart.js on backend I have followed chartjs-node-canvas
but getting TypeError: this._chartJs is not a constructor
My Chart.js version is 4.2.0 and chartjs-node-canvas version is 3.2.0
I think the versions are conflicting but not quite sure so please help me
Thanks in advance :)
Here's the code
const { ChartJSNodeCanvas } = require('chartjs-node-canvas');
const width = 400;
const height = 400;
const chartCallback = (ChartJS) => {};
const chartJSNodeCanvas = new ChartJSNodeCanvas({ width, height, chartCallback });
(async () => {
const configuration = {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [
{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}
]
},
options: {
scales: {
yAxes: [
{
ticks: {
beginAtZero: true,
callback: (value) => '$' + value
}
}
]
}
}
};
const image = await chartJSNodeCanvas.renderToBuffer(configuration);
const dataUrl = await chartJSNodeCanvas.renderToDataURL(configuration);
const stream = chartJSNodeCanvas.renderToStream(configuration);
})();
Related
I am not very experienced with JavaScript and have a bit of difficulty with chart.js I can't get the chart.js graph to appear. I've tried everything, but nothing; below I have left you a part of the code and the photo of how the "graph" looks. Thanks in advance
<h5 class="card-title">Line Chart</h5>
<div style="height: 400px">
<canvas id="line-char"></canvas>
<script>
const ctx = document.getElementById('myChart');
const ctx = document.getElementById('myChart').getContext('2d');
const ctx = $('#myChart');
const ctx = 'myChart';
</script>
<canvas id="line-char"></canvas>
<script>
const ctx = document.getElementById('line-char');
const line_char = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
‘rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
‘rgba(75, 192, 192, 1)',
‘rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
y: {
beginAtZero: true
}
}
}
});
</script>
Image link
Your chart configuration contains invalid characters in backgroundColor and borderColor (‘ instead of ').
‘rgba(75, 192, 192, 0.2)',
Please take a look at your amended and runnable code below and see how it works now.
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.7.0/chart.js"></script>
<h5 class="card-title">Line Chart</h5>
<div style="height: 400px">
<canvas id="line-char"></canvas>
<script>
new Chart('line-char', {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: ['rgba(255, 99, 132, 0.2)', 'rgba(54, 162, 235, 0.2)', 'rgba(255, 206, 86, 0.2)', 'rgba(75, 192, 192, 0.2)', 'rgba(153, 102, 255, 0.2)', 'rgba(255, 159, 64, 0.2)'],
borderColor: ['rgba(255, 99, 132, 1)', 'rgba(54, 162, 235, 1)', 'rgba(255, 206, 86, 1)', 'rgba(75, 192, 192, 1', 'rgba(153, 102, 255, 1)', 'rgba(255, 159, 64, 1)'],
borderWidth: 1
}]
},
options: {
scales: {
y: {
beginAtZero: true
}
}
}
});
</script>
</div>
I have here a smart contract and a I want to make a chart for this smart Contract address
0xE462CbEE0cd420f6c199B0194B1D8D93Fb5e7720 and for "total supply"
I want the chart to update as soon as a transaction goes in our out
How can i implement this in chartjs?
I have here the html canvas
<canvas id="myChart" width="400" height="400"></canvas>
and than the js file with this
var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
//and here is the data from my smart contract
var supply = await contract.methods.totalSupply().call()
// and than i output it in my UI like this
document.getElementById('contractBalanceSnet').innerHTML = supply/100000000
How can i now use the data totalSupply for the chart?
Html
<div class="chart-container" style="height:315px">
<canvas id="test"></canvas>
</div>
I've included these files
<script src="/assets/vendors/jquery/dist/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.24.0/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.min.js" type="text/javascript"></script>
<script src="/assets/js/test.js"></script>
test.js
$(document).ready(function() {
var ctx = document.getElementById('test').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
});
I used the sample code from https://www.chartjs.org/docs/latest/ for test.js. I'm also using laravel if that could have something to do with it.
Here's the error I'm getting.
Chart.min.js:7 Uncaught TypeError: Cannot read property 'fontSize' of
undefined
at Object._parseFont (Chart.min.js:7)
at i.fit (Chart.min.js:7)
at i.update (Chart.min.js:7)
at Chart.min.js:7
at Object.each (Chart.min.js:7)
at Object.update (Chart.min.js:7)
at ni.updateLayout (Chart.min.js:7)
at ni.update (Chart.min.js:7)
at ni.construct (Chart.min.js:7)
at new ni (Chart.min.js:7)
EDIT
Removing $(document).ready() fixed the problem
Please check this example jquery 2.2.4
// find elements
var ctx = document.getElementById('myChart');
var ctx = document.getElementById('myChart').getContext('2d');
var ctx = $('#myChart');
var ctx = 'myChart';
var ctx = document.getElementById('myChart');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.4/jquery.min.js"></script>
<canvas id="myChart" width="400" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.8.0/Chart.min.js" type="text/javascript"></script>
It works perfectly fine if you properly source the jQuery library.
Check here https://jsfiddle.net/g7qmh8wL/1/
// no code changes required.
I am implementing an application with codeigniter framework, I want to produce charts with Chart.JS, I have a controller an array with the data and I intend to send them to the javascript file with the graph implementation, and show everything in the view, but I can not pass the data.
Controller
function index() {
$data['DT'] = $this->Dashboard_main_model->get_dt_in();
$data['CL'] = $this->Dashboard_main_model->get_cl_in();
$data['MT'] = $this->Dashboard_main_model->get_mt_in();
$data['SN_AU'] = $this->Dashboard_main_model->get_sn_au_in();
$data['SN_AT'] = $this->Dashboard_main_model->get_sn_at_in();
$data['SN_MR'] = $this->Dashboard_main_model->get_sn_mr_in();
$data['DT_TMPs'] = $this->Dashboard_main_model->get_dt_tmp_in();
$data['CL_TMPs'] = $this->Dashboard_main_model->get_cl_tmp_in();
$data['_view'] = 'dashboard';
$this->load->view('layouts/main', $data);
}
JS FILE teste.js
var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
view
<div class="col-md-6">
<div class="box">
<div class="box-header">
<h3 class="box-title">Chamadas Atendidas</h3>
</div>
<div class="box-body no-padding">
<canvas id="myChart" style="auto;"></canvas>
</div>
</div>
</div>
</div>
Well I had a go at this and it seems the best bet is to install the Chart.min.js locally on your server - I grabbed it from Github - the link is on the chartjs.org site ( which you have obviously been to already)
Download it and save it where appropriate for your setup.
Controller - Chart.php
<?php
defined('BASEPATH') OR exit('No direct script access allowed');
class Chart extends CI_Controller {
public function __construct() {
parent::__construct();
}
public function index() {
$this->load->helper('url');
$this->load->view('chart_view');
}
}
View - chart_view.php
<canvas id="myChart"></canvas>
// Load the Chart.min.js locally on the server
// Note: make sure you have application/config/config.php config['base_url'] correctly set.
<script src="<?=base_url('assets/chart/2.8.0/Chart.min.js');?>"></script>
<script type="application/javascript">
let ctx = document.getElementById('myChart').getContext('2d');
let myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ['Red', 'Blue', 'Yellow', 'Green', 'Purple', 'Orange'],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255, 99, 132, 1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
</script>
And I got a nice little chart showing up.
See if that works for you.
var myCharts = <HTMLCanvasElement>document.getElementById("myChart");
var ctx = myCharts.getContext('2d');
var myChart = new Chart(ctx) => ({
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
backgroundColor: [
'rgba(255, 99, 132, 0.2)',
'rgba(54, 162, 235, 0.2)',
'rgba(255, 206, 86, 0.2)',
'rgba(75, 192, 192, 0.2)',
'rgba(153, 102, 255, 0.2)',
'rgba(255, 159, 64, 0.2)'
],
borderColor: [
'rgba(255,99,132,1)',
'rgba(54, 162, 235, 1)',
'rgba(255, 206, 86, 1)',
'rgba(75, 192, 192, 1)',
'rgba(153, 102, 255, 1)',
'rgba(255, 159, 64, 1)'
],
borderWidth: 1
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
// Please someone help me with this function. I am currently learning and not understanding whats wrong with this. The error says I am missing a semi colon at =>
Your problem is on this line:
var myChart = new Chart(ctx) => ({
This isn't valid JavaScript. My best guess is you meant something like this:
var myChart = new Chart(ctx, {