182
votes

I want to draw a horizontal bar chart with Chart.js but it keeps scaling the chart instead of using the height I assign the canvas form the script.

Is there any way to set the height of the graph from the script?

See fiddle: Jsfidle

HTML

<div class="graph">
  <div class="chart-legend">

  </div>
  <div class="chart">
    <canvas id="myChart"></canvas>
  </div>
</div>

JavaScript

var ctx = $('#myChart');

ctx.height(500);

var myChart = new Chart(ctx, {
    type: 'horizontalBar',
    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
        }]
    },
    maintainAspectRatio: false,
    options: {
        scales: {
            yAxes: [{
                ticks: {
                    beginAtZero:true
                }
            }]
        }
    }
});
12
You may update the ratio height vs width of your chart with this solution stackoverflow.com/questions/40594025/…Sylhare

12 Answers

85
votes

Seems like var ctx = $('#myChart'); is returning a list of elements. You would need to reference the first by using ctx[0]. Also height is a property, not a function.

I did it this way in my code:

var ctx = document.getElementById("myChart");
ctx.height = 500;
430
votes

If you disable the maintain aspect ratio in options then it uses the available height:

var chart = new Chart('blabla', {
                type: 'bar',
                data: {
                },
                options: {
                    maintainAspectRatio: false,
                }
            });
152
votes

The easiest way is to create a container for the canvas and set its height:

<div style="height: 300px">
  <canvas id="chart"></canvas>
</div>

and set

options: {  
    responsive: true,
    maintainAspectRatio: false
}
18
votes

You can wrap your canvas element in a parent div, relatively positioned, then give that div the height you want, setting maintainAspectRatio: false in your options

//HTML
<div id="canvasWrapper" style="position: relative; height: 80vh/500px/whatever">
<canvas id="chart"></canvas>
</div>

<script>
new Chart(somechart, {
options: {
    responsive: true,
    maintainAspectRatio: false

/*, your other options*/

}
});
</script>
15
votes

This one worked for me:

I set the height from HTML

canvas#scoreLineToAll.ct-chart.tab-pane.active[height="200"]
canvas#scoreLineTo3Months.ct-chart.tab-pane[height="200"]
canvas#scoreLineToYear.ct-chart.tab-pane[height="200"]

Then I disabled to maintaining aspect ratio

options: {
  responsive: true,
  maintainAspectRatio: false,
8
votes

You can also set the dimensions to the canvas

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

And then set the responsive options to false to always maintain the chart at the size specified.

options: {
    responsive: false,
}
6
votes

He's right. If you want to stay with jQuery you could do this

var ctx = $('#myChart')[0];
ctx.height = 500;

or

var ctx = $('#myChart');
ctx.attr('height',500);
5
votes

I created a container and set it the desired height of the view port (depending on the number of charts or chart specific sizes):

.graph-container {
width: 100%;
height: 30vh;
}

To be dynamic to screen sizes I set the container as follows:

*Small media devices specific styles*/
@media screen and (max-width: 800px) {
.graph-container {
        display: block;
        float: none;
        width: 100%;
        margin-top: 0px;
        margin-right:0px;
        margin-left:0px;
        height: auto;
    }
}

Of course very important (as have been referred to numerous times) set the following option properties of your chart:

options:{
    maintainAspectRatio: false,
    responsive: true,
}
4
votes

You should use html height attribute for the canvas element as:

<div class="chart">
    <canvas id="myChart" height="100"></canvas>
</div>
3
votes

Set the aspectRatio property of the chart to 0 did the trick for me...

    var ctx = $('#myChart');

    ctx.height(500);

    var myChart = new Chart(ctx, {
        type: 'horizontalBar',
        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
            }]
        },
        maintainAspectRatio: false,
        options: {
            scales: {
                yAxes: [{
                    ticks: {
                        beginAtZero:true
                    }
                }]
            }
        }
    });
myChart.aspectRatio = 0;
1
votes

Just to add on to the answer given by @numediaweb

In case you're banging your head against the wall because after following the instructions to set maintainAspectRatio=false: I originally copied my code from an example I got on a website on using Chart.js with Angular 2+:

        <div style="display: block">
          <canvas baseChart
                  [datasets]="chartData"
                  [labels]="chartLabels"
                  [options]="chartOptions"
                  [legend]="chartLegend"
                  [colors]="chartColors"
                  [chartType]="chartType">
          </canvas>
        </div>

To make this work correctly you must remove the embedded (and unnecessary) style="display: block" Instead define a class for the enclosing div, and define its height in CSS.

Once you do that, the chart should have responsive width but fixed height.

1
votes

Needed the chart to fill the parent element 100%, rather than setting height manually, and the problem was to force parent div to always fill remaining space.

After setting responsive and ratio options (check out related chartjs doc), the following css did the trick:

html

<div class="panel">
  <div class="chart-container">
    <canvas id="chart"></canvas>
  </div>
</div>

scss:

.panel {
  display: flex;

  .chart-container {
    position: relative;
    flex-grow: 1;
    min-height: 0;
  }
}