Chartjs to add phases in line chart - Javascript Chart.js

Javascript examples for Chart.js:Line Chart

  1. HOME
  2. Javascript
  3. Chart.js
  4. Line Chart

Description

Chartjs to add phases in line chart

Demo Code

ResultView the demo in separate window 

<html>
   <head> 
      <meta name="viewport" content="width=device-width, initial-scale=1"> 
      <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.2.2/Chart.min.js"></script> 
      <script type="text/javascript">
    window.onload=function(){/*w  w w.jav  a 2s .  co m*/
var ctx = document.getElementById("canvas");
var phasePlugin = {
    afterDraw: function(chart)
    {
        var ctx = chart.chart.ctx;
        var xAxeId = chart.config.options.scales.xAxes[0].id;
        var xAxe = chart.scales[xAxeId];
        var yAxeId = chart.config.options.scales.yAxes[0].id;
        var yAxe = chart.scales[yAxeId];
        var ticks = xAxe.ticks;
        var phases = chart.config.options.scales.xAxes[0].phases;
        for (var i = 0; i < phases.length; i++) {
           if (ticks.indexOf(phases[i].from) == -1 || (ticks.indexOf(phases[i].to) == -1))
               continue;
            var xPos = ((xAxe.width - xAxe.paddingRight) / xAxe.maxIndex) * ticks.indexOf(phases[i].from) + xAxe.left + 1;
            ctx.setLineDash([8, 8]);
            ctx.strokeStyle = phases[i].color;
            ctx.strokeRect(xPos, yAxe.top, 0, yAxe.height);
            xPos = ((xAxe.width - xAxe.paddingRight) / xAxe.maxIndex) * ticks.indexOf(phases[i].to) + xAxe.left + 1;
            ctx.strokeStyle = phases[i].color;
            ctx.strokeRect(xPos, yAxe.top, 0, yAxe.height);
            ctx.setLineDash([1,0]);
        }
    }
};
Chart.pluginService.register(phasePlugin);
var data = {
    labels: ["January", "February", "March", "April", "May", "June", "July"],
    datasets: [
        {
            label: "My First dataset",
            fill: false,
            lineTension: 0.1,
            backgroundColor: "rgba(75,192,192,0.4)",
            borderColor: "rgba(75,192,192,1)",
            borderCapStyle: 'butt',
            borderDash: [],
            borderDashOffset: 0.0,
            borderJoinStyle: 'miter',
            pointBorderColor: "rgba(75,192,192,1)",
            pointBackgroundColor: "#fff",
            pointBorderWidth: 1,
            pointHoverRadius: 5,
            pointHoverBackgroundColor: "rgba(75,192,192,1)",
            pointHoverBorderColor: "rgba(220,220,220,1)",
            pointHoverBorderWidth: 2,
            pointRadius: 1,
            pointHitRadius: 10,
            data: [65, 59, 80, 81, 56, 55, 40],
            spanGaps: false,
        }
    ]
};
var myLineChart = new Chart(ctx, {
    type: 'line',
    data: data,
    options: {
       scales: {
            xAxes: [{
                phases: [{
                   from: "January",
                    to: "March",
                    color: "blue"
                },
                {
                   from: "May",
                    to: "June",
                    color: "red"
                }]
            }]
        }
    }
});
    }

      </script> 
   </head> 
   <body> 
      <canvas id="canvas" height="200"></canvas>  
   </body>
</html>

Related Tutorials