[Chartjs]-How can I control the placement of my Chart.JS pie chart's legend, as well as its appearance?

by

2đź‘Ť

âś…

This is what works (more or less) using version 2 of Chart.JS:

HTML

<h2 class="sectiontext">Top 10 Items</h2>
<br />
<div class="chart">
    <canvas id="top10ItemsChart" class="pie"></canvas>
    <div id="pie_legend"></div>
</div>

JQUERY

var data = {
    labels: [
        "Bananas: 2,755 (18%)",
        "Lettuce, Romaine: 2,256 (14%)",
        "Melons, Watermelon: 1,637 (10%)",
        "Pineapple: 1,608 (10%)",
        "Berries: 1,603 (10%)",
        "Lettuce, Spring Mix: 1,433 (9%)",
        "Broccoli: 1,207 (8%)",
        "Melons, Honeydew: 1,076 (7%)",
        "Grapes: 1,056 (7%)",
        "Melons, Cantaloupe: 1,048 (7%)"
    ],
    datasets: [
        {
            data: [2755, 2256, 1637, 1608, 1603, 1433, 1207, 1076, 1056, 1048],
            backgroundColor: [
                "#FFE135",
                "#3B5323",
                "#fc6c85",
                "#ffec89",
                "#021c3d",
                "#3B5323",
                "#046b00",
                "#cef45a",
                "#421C52",
                "#FEA620"
            ],
        }]
};

var optionsPie = {
    responsive: true,
    scaleBeginAtZero: true
}

var ctx = $("#top10ItemsChart").get(0).getContext("2d");
var top10PieChart = new Chart(ctx,
{
    type: 'pie',
    data: data,
    options: optionsPie
});

$("#top10Legend").html(top10PieChart.generateLegend());

I say, “more or less” because the pie pieces are still pitifully puny:

enter image description here

19đź‘Ť

I think this what you want: DEMO

First, you need to make canvas responsive by overriding fixed width and height and wrap it in additional div that can be used for positioning. I used display: table for centering elements but setting inner divs to inline-block also works if you wish for chart and legend to take different amount of space than 50:50.

HTML:

<div class="table">
    <div class="cell">
        <canvas id="top10ItemsChart" class="pie"></canvas>
    </div>
    <div class="cell" id="top10Legend"></div>
</div>

CSS:

canvas {
    width: 100% !important;
    height: auto !important;
}

.table {
    border: 1px solid red;
    display: table;
    width: 100%;
    table-layout: fixed;
}

.cell {
    display: table-cell;
    vertical-align: middle;
}

UPDATE: Did some adjustment based on additional information by OP NEW DEMO

HTML:

<div class="container">
<div class="row">
<div class="col-md-6">
    <div class="topleft">
        <h2 class="sectiontext">Top 10 Items</h2>
        <br />
        <div class="chart">
            <div class="pie">
                <canvas id="top10ItemsChart" class="pie"></canvas>
            </div>
            <div class="legend" id="top10Legend">
            </div>
        </div>
    </div>
</div>
</div>
</div>

CSS:

    .topleft {
        margin-top: -4px;
        margin-left: 16px;
        margin-bottom: 16px;
        padding: 16px;
        border: 1px solid black;
    }

canvas {
    width: 100% !important;
    height: auto !important;
    margin-left: -25%;
}

.chart {
    border: 1px solid forestgreen;
    width: 100%;
    overflow: hidden;
    position: relative;
}

.pie {
    position: relative;
    padding: 10px 0;
    // adjust as necessary
    padding-left: 10px;
    padding-right: 0;
}

.legend {
    position: absolute;
    right: 10px;
    top: 10px;
    height: 100%;
    // adjust as necessary:
    width: 48%;
}

@media (max-width: 480px) {
    .legend {
        position: relative;
        width: 100%;
    }
    .pie {
        margin: 0;
    }
}

.pie-legend ul {
    list-style: none;
    margin: 0;
    padding: 0;
    width: 300px;
}

.pie-legend span {
    display: inline-block;
    width: 14px;
    height: 12px;
    border-radius: 100%;
    margin-right: 4px;
    margin-bottom: -2px;
}

.pie-legend li {
    margin-bottom: 4px;
    display: inline-block;
    margin-right: 4px;
}

3đź‘Ť

As @B.ClayShannon mentioned, version 2 is quite a bit different than verison 1. Here is an example of how to customize the legend template using version 2. 

options: {
    legendCallback: function (chart) {
        var text = [];
        text.push('<ul class="' + chart.id + '-legend" style="list-style:none">');
        for (var i = 0; i < chart.data.datasets[0].data.length; i++) {
            text.push('<li><div style="width:10px;height:10px;display:inline-block;background:' + chart.data.datasets[0].backgroundColor[i] + '" />&nbsp;');
            if (chart.data.labels[i]) {
                text.push(chart.data.labels[i]);
            }
            text.push('</li>');
        }
        text.push('</ul>');

        return text.join('');
    },
    legend: {display: false},
}

It’s not shown directly in the accepted solution above, but to render your legend elsewhere you’ll want to call:

$("#myChartLegend").html(myChart.generateLegend());

Finally, some HTML to pull it together (note clearfix is a Bootstrap class that :

<div class="chart">
    <div style="float:left">
        <canvas id="myChart" class="pie" style="max-width:300px;"></canvas>
    </div>

    <div class="legend" id="myChartLegend" style="float:left;"></div>
    <div style="clear: both;"/>
</div>

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