Chartjs-Chart.js Second hidden value for Bar Chart

2👍

You can define your data in object format and then you can just add a custom property that you read in the onClick method like so:

var options = {
  type: 'bar',
  data: {
    labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
    datasets: [{
        label: '# of Votes',
        data: [{
            x: "Red",
            y: 12,
            secretVal: "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
          },
          {
            x: "Blue",
            y: 19,
            secretVal: "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
          },
          {
            x: "Yellow",
            y: 3,
            secretVal: "Not rick roll"
          },
          {
            x: "Green",
            y: 5,
            secretVal: "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
          },
          {
            x: "Purple",
            y: 2,
            secretVal: "Not rick roll"
          },
          {
            x: "Orange",
            y: 3,
            secretVal: "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
          }
        ],
        backgroundColor: 'pink'
      },
      {
        label: '# of Points',
        data: [{
            x: "Red",
            y: 7,
            secretVal: "Not rick roll"
          },
          {
            x: "Blue",
            y: 11,
            secretVal: "https://www.youtube.com/watch?v=dQw4w9WgXcQ"
          },
          {
            x: "Yellow",
            y: 5,
            secretVal: "Not rick roll"
          },
          {
            x: "Green",
            y: 8,
            secretVal: "Not rick roll"
          },
          {
            x: "Purple",
            y: 3,
            secretVal: "Not rick roll"
          },
          {
            x: "Orange",
            y: 7,
            secretVal: "Not rick roll"
          }
        ],
        backgroundColor: 'orange'
      }
    ]
  },
  options: {
    onClick: (e, activeEls, chart) => {
      if (activeEls.length === 0) {
        return;
      }
      const cEl = activeEls[0];
      console.log(chart.data.datasets[cEl.datasetIndex].data[cEl.index].secretVal)
    }
  }
}

var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
  <canvas id="chartJSContainer" width="600" height="400"></canvas>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.7.0/chart.js"></script>
</body>

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