chart.js Adding Percantage Sign on Tooltip

Question

    var dmgchartt = document.getElementById("dmgchart");
    new Chart(dmgchartt, {
    type: "radar",
    data: radarChartData0,
    options: {
             tooltipTemplate: "<%if (label){%><%=label %>: <%}%><%= value + ' %' %>",
              scale: {
                ticks: {
                    beginAtZero: true
                }
            },
            title: {
            display: true,
            text: 'Title'
        }
    }
});

It just shows the value without percentage sign. I tried to add percentage sign after value on tooltip but it didn't work. Also how can i choose if tooltip is multi or single? I have 2 datasets.

Answer 1

If you're using Chart.js 2.0 as suggested by @xnakos in the comments you have to use options.tooltips.callbacks.label

 var dmgchartt = document.getElementById("dmgchart");
 new Chart(dmgchartt, {
        type: 'radar',
        data: data,
        options: {
            tooltips: {
                mode: 'label',
                callbacks: {
                    label: function(tooltipItem, data) {
                        return data['datasets'][0]['data'][tooltipItem['index']] + '%';
                    }
                }
            },
          scale: {
            ticks: {
                beginAtZero: true
            }
        },
        title: {
        display: true,
        text: 'Title'
    }

    }
    });