charts - ChartsJS: Custom tooltip always displaying -


im using chartjs create graph on website.

im trying create custom tooltip. according documentation, should easy: 

var mypiechart = new chart(ctx, {     type: 'pie',     data: data,     options: {         tooltips: {             custom: function(tooltip) {                 // tooltip false if tooltip not visible or should hidden                 if (!tooltip) {                     return;                 }         }       }     }   });

my problem tooptip never false , because of custom tooltip displayed.

please see jsfiddle (line 42 never executed)

question: bug tooltip never false, or missing something?

the custom tooltip option used when want create/style own tooltip using htlm/css outside of scope of canvas (and not use built in tooltips @ all).

in order this, must define place outside of canvas contain tooltip (e.g. div) , use container within tooltips.custom function.

here example used custom tooltip display hovered pie chart section percentage in middle of chart. in example i'm generating tooltip inside div id "chartjs-tooltip". notice how interact div in tooltips.custom function position , change value.

also, correct way check if tooltip should hidden check it's opacity. tooltip object exist, when should not visible, opacity set 0.

chart.defaults.global.tooltips.custom = function(tooltip) {   // tooltip element   var tooltipel = document.getelementbyid('chartjs-tooltip');    // hide if no tooltip   if (tooltip.opacity === 0) {     tooltipel.style.opacity = 0;     return;   }    // set text   if (tooltip.body) {     var total = 0;      // value of datapoint     var value = this._data.datasets[tooltip.datapoints[0].datasetindex].data[tooltip.datapoints[0].index].tolocalestring();      // calculate value of datapoints   this._data.datasets[tooltip.datapoints[0].datasetindex].data.foreach(function(e) {       total += e;     });      // calculate percentage , set tooltip value     tooltipel.innerhtml = '<h1>' + (value / total * 100) + '%</h1>';   }    // calculate position of tooltip   var centerx = (this._chartinstance.chartarea.left + this._chartinstance.chartarea.right) / 2;   var centery = ((this._chartinstance.chartarea.top + this._chartinstance.chartarea.bottom) / 2);    // display, position, , set styles font   tooltipel.style.opacity = 1;   tooltipel.style.left = centerx + 'px';   tooltipel.style.top = centery + 'px';   tooltipel.style.fontfamily = tooltip._fontfamily;   tooltipel.style.fontsize = tooltip.fontsize;   tooltipel.style.fontstyle = tooltip._fontstyle;   tooltipel.style.padding = tooltip.ypadding + 'px ' + tooltip.xpadding + 'px'; };

here full codepen example.

i hope helps clear things up!


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