Chart.js - 样式图例

I'm making a chart with chart.js and I'm trying to figure out how I can change the label/legend styling. I want to remove the rectangle part and instead use a circle. I've read that you can make your custom legend (using legendCallback), but for the life of me I cannot figure out how to do it. This is how my chart looks now - image.

This is my HTML:

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

And this is my JS:

var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
    type: 'line',
    data: {
        labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
        datasets: [{
            label: 'Link One',
            data: [1, 2, 3, 2, 1, 1.5, 1],
            backgroundColor: [
                '#D3E4F3'
            ],
            borderColor: [
                '#D3E4F3',
                '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: {
        legend: {
            display: true,
          position: 'bottom',
            labels: {
                fontColor: '#333',
            }
        }
}
});

I'm new to JS in general, so please be as specific as possible with your answers. Thank you so much!

解决方案

No need to use legendCallback function. You can set usePointStyle = true to turn that rectangle into a circle.

Chart.defaults.global.legend.labels.usePointStyle = true;

var ctx = document.getElementById("myChart").getContext("2d");
var myChart = new Chart(ctx, {
    type: 'line',
    data: {
        labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
        datasets: [{
            label: 'Link One',
            data: [1, 2, 3, 2, 1, 1.5, 1],
            backgroundColor: [
                '#D3E4F3'
            ],
            borderColor: [
                '#D3E4F3',
                '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: {
        legend: {
            display: true,
            position: 'bottom',
            labels: {
                fontColor: '#333'
            }
        }
    }
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.5.0/Chart.min.js"></script>
<div class="container">
  <canvas id="myChart"></canvas>
</div>