event handler on center of doughnut chart - Javascript Chart.js

Javascript examples for Chart.js:Doughnut Chart

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Description

event handler on center of doughnut chart

Demo Code

ResultView the demo in separate window 

<html>
   <head> 
      <title>Chart.js version 2 responsive doughnut with text inside</title> 
      <meta name="viewport" content="width=device-width, initial-scale=1"> 
      <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.1.6/Chart.bundle.js"></script> 
      <script type="text/javascript">
    window.onload=function(){//from  w  ww .  j  a  v  a 2s. co  m
var data = {
  labels: [
    "Red",
    "Blue",
    "Yellow"
  ],
  datasets: [
    {
      data: [300, 50, 100],
      backgroundColor: [
        "#FF6384",
        "#36A2EB",
        "#FFCE56"
      ],
      hoverBackgroundColor: [
        "#FF6384",
        "#36A2EB",
        "#FFCE56"
      ]
    }]
};
var promisedDeliveryChart = new Chart(document.getElementById('myChart'), {
  type: 'doughnut',
  data: data,
  options: {
     responsive: true,
    legend: {
      display: false
    }
  }
});
Chart.pluginService.register({
  beforeDraw: function(chart) {
    var width = chart.chart.width,
        height = chart.chart.height,
        ctx = chart.chart.ctx;
    ctx.restore();
    var fontSize = (height / 114).toFixed(2);
    ctx.font = fontSize + "em sans-serif";
    ctx.textBaseline = "middle";
    var text = "75%",
        textX = Math.round((width - ctx.measureText(text).width) / 2),
        textY = height / 2;
    ctx.fillText(text, textX, textY);
    ctx.save();
  }
});
    }

      </script> 
   </head> 
   <body> 
      <canvas id="myChart"></canvas>  
   </body>
</html>

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