javascript - chart.js Failed to create chart: can't acquire context from the given item

Question

I never got into node so I am pretty sure I am doing something massively wrong here since I cannot find any info at all by googling.

I have a django site and I wanted a JS charting library, I chose chart.js.

I installed and like the docs, but after that I am unsure of what to do so I tried to fill in the blanks and follow their guide as much as possible. Here is what my html looks like....

<script src="/public/node_modules/chart.js/dist/Chart.js"></script>

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

<script>    
    var ctx = document.getElementById("myChart");
    console.log(ctx);

    var options = {}

    var data = {
        labels: ["January", "February", "March", "April", "May", "June", "July"],
        datasets: [
            {
                label: "My First dataset",
                fill: false,
                lineTension: 0.1,
                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: 5,
                pointHoverBackgroundColor: "rgba(75,192,192,1)",
                pointHoverBorderColor: "rgba(220,220,220,1)",
                pointHoverBorderWidth: 2,
                pointRadius: 1,
                pointHitRadius: 10,
                data: [65, 59, 80, 81, 56, 55, 40],
                spanGaps: false,
            }
        ]
    };

    var myChart = new Chart({
        type: 'line',
        data: data,
        options: options
    })
</script>

I am just trying to get an example working. I put the node_modules directory that was downloaded via npm somewhere where my server would serve them up....and verified they are being served, but then I get this error when I try to build a chart. I took all the chart codes from their docs so I am pretty sure that part is right, but I can't see why I am getting this error.

Answer 1

Another reason to get the same error, is if the element referred by the id is not a <canvas>. I had a <div> element in my HTML source, and of course it did not work.