Chart.js - show tooltip when hovering on legend

问题

I recently upgraded my version of Chart.js from v2.3 to v2.7.1, which broke an existing functionality where the specified segment in a doughnut chart would be active (hover color, tooltip shown) when the user hovered over the corresponding legend item. That code looked like this:

 var " + ClientID + @" = new Chart(" + ClientID + @"CTX, {
    data: { ... },
    options: {
        legend: {
            onHover: function(evt, legendItem) {
                var index = " + ClientID + @".data.labels.indexOf(legendItem.text);
                if (" + ClientID + @".data.datasets[0].data[index] > 0) {
                    var metaData = " + ClientID + @".getDatasetMeta(0);
                    var activeSegment = metaData.data[index];
                    " + ClientID + @".tooltipActive = [activeSegment];
                    " + ClientID + @".active = [activeSegment];
                }                                   
            },
        }
    }
});

Looking through the Chart.js file and documentation, it looks like the tooltipActive property has been completely removed, thus breaking the legend hover functionality. I looked through the release notes and PRs on the Chart.js git but couldn't find where this was noted as a breaking change, or any mention of it whatsoever. I have to upgrade versions of Chart.js for a separate change I'm making, so reverting back to v2.3 is not an option. Has anyone else run into this?

来源：https://stackoverflow.com/questions/48569325/chart-js-show-tooltip-when-hovering-on-legend