Add shadow Chart.js

Question

I'm using the last version of chart.js and I want to add a shadow to each bar

Here's an example of code

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

<script> 
var ctx = document.getElementById("myChart").getContext('2d');
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
                }
            }]
        }
    }
});
</script>

Can you make the title a bit more specific? – vsync Sep 09 '17 at 10:36 — vsync, Sep 09 '17 at 10:36

Mehraj Khan · Answer 1 · 2017-09-09T11:03:52.727

1

This will work for the line chart.

[Edited...]

Chart.types.Line.extend({
  name: "LineAlt",
  initialize: function () {
    Chart.types.Line.prototype.initialize.apply(this, arguments);

    var ctx = this.chart.ctx;
    var originalStroke = ctx.stroke;
    ctx.stroke = function () {
      ctx.save();
      ctx.shadowColor = '#000';
      ctx.shadowBlur = 10;
      ctx.shadowOffsetX = 8;
      ctx.shadowOffsetY = 8;
      originalStroke.apply(this, arguments)
      ctx.restore();
    }
  }
});

var data = {
  labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
  datasets: [
    {
      fillColor: "rgba(255, 99, 132, 0.2)",
      strokeColor: "rgba(54, 162, 235, 0.2)",
      pointColor: "rgba(255, 206, 86, 0.2)",
      pointStrokeColor: "#fff",
      pointHighlightFill: "#fff",
      pointHighlightStroke: "rgba(75, 192, 192, 0.2)",
      data: [12, 19, 3, 5, 2, 3]
    }
  ]
};

var ctx = document.getElementById("myChart").getContext("2d");
var canvas = new Chart(ctx).LineAlt(data, {
  datasetFill: false
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.0.2/Chart.min.js"></script>
<canvas id="myChart" width="600" height="300"></canvas>

Appreciate if useful

edited Sep 09 '17 at 11:03

answered Sep 09 '17 at 10:32

Mehraj Khan

927
6
17

I made the required changes check them out. – Mehraj Khan Sep 09 '17 at 11:05
Ok, thank you. Just a thing the options of my chart, where can I write them? – user8583676 Sep 09 '17 at 11:37
After variable ctx creation, `var ctx = document.getElementById("myChart").getContext('2d');` you have to replace this script.I did completely include options. – Mehraj Khan Sep 09 '17 at 11:54
Ok yeah it was easy at the end to edit. Just a question, if I have two lines, one red and one blue, do you know how to make the shadow the same color as the line? – user8583676 Sep 09 '17 at 16:25
yes, you can create a variable of the second line and apply required functionalities what you want.Appreciate if above snippet is useful :) – Mehraj Khan Sep 12 '17 at 07:47

uminder · Answer 2 · 2020-09-23T11:50:15.230

Based on this answer, I created a runnable code snippet that illustrates how to create bars with shadows.

const dataset = [40, 80, 50, 60, 70];
const offset = 8;

Chart.pluginService.register({
  afterUpdate: function(chart) {
      var metaData = chart.getDatasetMeta(0).data;
      for (var i = 0; i < metaData.length; i++) {
          var model = metaData[i]._model;
          model.x += offset;
          model.controlPointNextX += offset;
          model.controlPointPreviousX += offset;
      }
  }
});

var data = {
    labels: ["A", "B", "C", "D", "E"],
    datasets: [{
            backgroundColor: [
              'rgba(255, 99, 132)',
              'rgba(255, 206, 86)',
              'rgba(54, 162, 235)',              
              'rgba(75, 192, 192)',
              'rgba(153, 102, 255)'
              ],
            borderWidth: 1,
            data: dataset,
            xAxisID: "bar-x-axis1",
            categoryPercentage: 0.5,
            barPercentage: 0.5,
        },
        {
            backgroundColor: 'rgba(0, 0, 0, 0.2)',
            data: dataset.map(v => v + offset),
            xAxisID: "bar-x-axis2",
            categoryPercentage: 0.5,
            barPercentage: 0.5
        }
    ]
};

var options = {  
    legend: {
        display: false
    },
    tooltips: {
        enabled: false
    },
    scales: {        
        xAxes: [
            {
                id: "bar-x-axis2"
            },
            {
                id: "bar-x-axis1",              
                offset: true,
                display: false
           }
        ],
        yAxes: [{
            id: "bar-y-axis1",
            ticks: {
                beginAtZero: true,
                stepSize: 50
            }
        }]
    }
};

var ctx = document.getElementById("myChart").getContext("2d");
var myBarChart = new Chart(ctx, {
    type: 'bar',
    data: data,
    options: options
});

<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<canvas id="myChart" height="60"></canvas>

Add shadow Chart.js

2 Answers2

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