[Chartjs]-ChartJS – Different color per data point

In updating to version 2.2.2 of ChartJS, I found that the accepted answer no longer works. The datasets will take an array holding styling information for the properties.
In this case:

var pointBackgroundColors = [];
var myChart = new Chart($('#myChart').get(0).getContext('2d'), {
    type: 'line',
    data: {
        datasets: [
            {
                data: dataPoints,
                pointBackgroundColor: pointBackgroundColors
            }
        ]
    }
});

for (i = 0; i < myChart.data.datasets[0].data.length; i++) {
    if (myChart.data.datasets[0].data[i] > 100) {
        pointBackgroundColors.push("#90cd8a");
    } else {
        pointBackgroundColors.push("#f58368");
    }
}

myChart.update();

I found this looking through the samples for ChartJS, specifically this one: “Different Point Sizes Example”

With recent versions of chart.js I would recommend doing this with scriptable options.

Scriptable options give you an easy way to vary the style of a dataset property (e.g. line point colour) dynamically according to some function you provide. Your function is passed a ‘context’ object that tells it the index and value of the point etc. (see below).

Most chart properties can be scripted; the dataset properties for each chart type tell you the exact list (e.g. see here for line chart).

Here is how you might use scriptable options on a line chart (based on the example in the docs). On this chart negative data points are shown in red, and positive ones in alternating blue/green:

window.myChart = Chart.Line(ctx, {
    data: {
        labels: x_data,
        datasets: [
            {
                data: y_data,
                label: "Test Data",
                borderColor: "#3e95cd",
                fill: false,
                pointBackgroundColor: function(context) {
                    var index = context.dataIndex;
                    var value = context.dataset.data[index];
                    return value < 0 ? 'red' :  // draw negative values in red
                        index % 2 ? 'blue' :    // else, alternate values in blue and green
                            'green';
                }
            }
        ],
    }
});

The context object passed to your function can have the following properties. Some of these won’t be present for certain types of entity, so test before use.

• chart: the associated chart
• dataIndex: index of the current data
• dataset: dataset at index datasetIndex
• datasetIndex: index of the
  current dataset
• hover: true if hovered

Here’s what worked for me (v 2.7.0), first I had to set pointBackgroundColor and pointBorderColor in the dataset to an array (you can fill this array with colours in the first place if you want):

var myChart = new Chart(ctx, {
    type: 'line',
    data: {
        datasets: [
            {
                data: dataPoints,
                pointBackgroundColor: [],
                pointBorderColor: [],
            }
        ]
    }
});

Then you can monkey with the colours of the points directly:

  myChart.data.datasets[0].pointBackgroundColor[4] = "#cc00cc";
  myChart.data.datasets[0].pointBorderColor[4] = "#cc0000";
  myChart.update();

Some other properties to play with to distinguish a point: pointStrokeColor (it apparently exists but I can’t seem to get it to work), pointRadius & pointHoverRadius (integers), pointStyle (‘triangle’, ‘rect’, ‘rectRot’, ‘cross’, ‘crossRot’, ‘star’, ‘line’, and ‘dash’), though I can’t seem to figure out the defaults for pointRadius and pointStyle.

Just adding what worked for me in the new 2.0 version.

Instead of:

myLineChart.datasets[0].points[4].fillColor =  "lightgreen";

I had to use:

myChart.config.data.datasets[0].backgroundColor[4] = "lightgreen";

Not sure if that’s because of a change in 2.0 or because I’m using a bar chart and not a line chart.

If you initialize the myChart in this manner,

var myChart = new Chart(ctx, {
  type: 'line',
  data: {

you have to change line color by this code

  myChart.data.datasets[0].backgroundColor[0] ="#87CEFA";

If you initialize the myChart in this manner,

myBar = new Chart(ctx).Line(barChartData, {

you have to change line color by this code

myLineChart.datasets[0].points[4].fillColor =  "#FF0000";

most of the ways were too complex for me so here’s how is solved it:
I am using react btw, so in the data parameter i was doing this

Before:

datasets:[
        {
            label: 'Maximum Predicted Temperature',
            fill: false,
            lineTension: 0.5,
            backgroundColor: ['red'],
            borderColor: 'rgba(0,0,0,1)',
            borderWidth: 2,
            data: max
        },

After:

datasets:[
        {
            label: 'Maximum Predicted Temperature',
            fill: false,
            lineTension: 0.5,
            backgroundColor: ['red','blue','green','yellow','orange','purple','pink','brown','grey','black','white','violet'],
            borderColor: ['red','blue','green','yellow','orange','purple','pink','brown','grey','black','white','violet'],
            borderWidth: 2,
            data: max
        }

the color will loop if your given data points are more than the number of colors provided and the color red will apply on every 12th data point it really helped me thought the solution is bit clumsy but gives more control hope this helps