[Chartjs]-OnClick event to Hide dataset Chart.js V2

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So, I got it right following this Post

Here is the code of the post

var weightChartOptions = {
        responsive: true,
        legendCallback: function(chart) {
            console.log(chart);
            var legendHtml = [];
            legendHtml.push('<table>');
            legendHtml.push('<tr>');
            for (var i=0; i<chart.data.datasets.length; i++) {
                legendHtml.push('<td><div class="chart-legend" style="background-color:' + chart.data.datasets[i].backgroundColor + '"></div></td>');                    
                if (chart.data.datasets[i].label) {
                    legendHtml.push('<td class="chart-legend-label-text" onclick="updateDataset(event, ' + '\'' + chart.legend.legendItems[i].datasetIndex + '\'' + ')">' + chart.data.datasets[i].label + '</td>');
                }                                                                              
            }                                                                                  
            legendHtml.push('</tr>');                                                          
            legendHtml.push('</table>');                                                       
            return legendHtml.join("");                                                        
        },                                                                                     
        legend: {                                                                              
            display: false                                                                     
        }                                                                                      
    };                                                                                         

    // Show/hide chart by click legend
    updateDataset = function(e, datasetIndex) {
        var index = datasetIndex;
        var ci = e.view.weightChart;
        var meta = ci.getDatasetMeta(index);

        // See controller.isDatasetVisible comment
        meta.hidden = meta.hidden === null? !ci.data.datasets[index].hidden : null;

        // We hid a dataset ... rerender the chart
        ci.update();
    };

    var ctx = document.getElementById("weightChart").getContext("2d");
    window.weightChart = new Chart(ctx, {
        type: 'line',
        data: weightChartData, 
        options: weightChartOptions
    });
    document.getElementById("weightChartLegend").innerHTML = weightChart.generateLegend();
};

the secret here is the legendCallback in line 3

In this example he uses line chart, in my case I used bars

So i changed the table tags for list tags for me worked better this way

He emphasizes to put "window" before the variable who gets the "= new Chart"

window.weightChart = new Chart(ctx, {…..

Then with a little of CSS you can get a nice legend with a hide/show option

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