Uncaught TypeError: Cannot read property 'offsetWidth' of undefined - chart.js

Question

I have this simple html:

<canvas id="myChart" width="400" height="400"></canvas>

and this js:

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
                    }
                }]
            }
        }
    });

Even though the canvas is configured with myChart id, I get the following error:

Uncaught TypeError: Cannot read property 'offsetWidth' of undefined

JSFiddle: https://jsfiddle.net/kroejrhx/

Answer 1

After revisiting the question, here's your problem: you are using the wrong version of chart.js. According to this section, if you want to use an axis that's time based, you either need to explicitly include moment.js, or use the bundle version.

Changing the resource in your jsfiddle to https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.1.4/Chart.bundle.min.js will show the expected chart. No need to change the code at all.

Answer 2

If you want to use Chart.js v2.0 then this CDN will work.

https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.1.3/Chart.bundle.min.js

Answer 3

You have to use the version 2 of chart.js. If you are using npm, in your package.json, update chart.js e.g., "chart.js": "^2.1.1",. In case you use react-chartjs-2, you will still need to make sure that your chart.js version is 2 or bigger.

Answer 4

Use this : var ctx = document.getElementById("myChart").getContext("2d");

Instead of : var ctx = document.getElementById("myChart");