[Chartjs]-Highlight doughnut segment on mouseenter generateLegend Chartjs 2

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3👍

✅

You can use the following function to highlight the corresponding segment of a doughnut chart, when hovered over a custom legend item :

function highlightSegment(chart, index, isHighlight) {
   var activeSegment = chart.getDatasetMeta(0).data[index];
   if (isHighlight) chart.updateHoverStyle([activeSegment], null, true);
   else chart.updateHoverStyle([activeSegment], null, false);
   chart.draw();
}

But, first you need to attach two event-listeners (mouseenter and mouseleave) to each of your li (legend) elements/items and then call the above function, passing the chart-instance, legend-item-index and a boolean value (whether to add/remove highlight), as the first, second and third arguments respectively.

ᴡᴏʀᴋɪɴɢ ᴇxᴀᴍᴘʟᴇ ⧩

var outerCircle = new Chart(document.getElementById("outer-circle"), {
   "type": "doughnut",
   "data": {
      "labels": ["Beer", "Wine", "Pisco", "Vodka", "Rum", "Tequila"],
      "datasets": [{
         "label": "Drinks",
         "data": [
            30,
            20,
            5,
            15,
            15,
            15
         ],
         "backgroundColor": [
            "#fdc694",
            "#ad937c",
            "#d8c2ae",
            "#bab8b6",
            "#e5aa74",
            "#fcf0e5"
         ]
      }]
   },
   "options": {
      "legend": {
         "display": false
      },
      "tooltips": {
         "mode": 'label',
         "callbacks": {
            "label": function(tooltipItem, data) {
               return " " + data['labels'][tooltipItem['index']] + " " + data['datasets'][0]['data'][tooltipItem['index']] + '%';
            }
         }
      }
   }
});

var diagramLegend = document.getElementById('diagram-legend');

diagramLegend.innerHTML = outerCircle.generateLegend();

/*** Highlight Doughnut Segment on Legend Hover ***/

var legendItems = document.querySelectorAll('#diagram-legend li');

legendItems.forEach(function(item, itemIndex) {
   item.addEventListener('mouseenter', function() {
      highlightSegment(outerCircle, itemIndex, true);
   });
   item.addEventListener('mouseleave', function() {
      highlightSegment(outerCircle, itemIndex, false);
   });
});

function highlightSegment(chart, index, isHighlight) {
   var activeSegment = chart.getDatasetMeta(0).data[index];
   if (isHighlight) chart.updateHoverStyle([activeSegment], null, true);
   else chart.updateHoverStyle([activeSegment], null, false);
   chart.draw();
}
#pie-wrapper {
   width: 300px;
   height: 300px;
}

#diagram-legend ul {
   list-style: none;
   padding: 0;
   margin: 0;
}

#diagram-legend ul li {
   margin-bottom: 10px;
}

#diagram-legend ul li span {
   width: 15px;
   height: 15px;
   display: inline-block;
   vertical-align: sub;
   margin-right: 10px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<div id="pie-wrapper">
   <canvas id="outer-circle" width="300" height="300"></canvas>
</div>
<div id="diagram-legend"></div>

0👍

    color: [
      {
        backgroundColor: ['#92d06f', '#73c8b8', '#3bb9ab'],
        borderColor: 'rgba(255, 255, 255, 0)',
        hoverBackgroundColor: ['#92d06f', '#73c8b8', '#3bb9ab'],
        hoverBorderColor: ['#92d06f', '#73c8b8', '#3bb9ab'],
        hoverBorderWidth: 10,
        hoverRadius: 0
      }
   ],

It Works fine on mouse enter highlights the active segment in angular 2 (ng2 charts) for doughnut chart

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