Highcharts - draw line chart with summed values but show breakup on hover - ajax

Question

I am using Highcharts - Line - Ajax.
Let's say I have two series of data - 'Headcount 1' and 'Headcount 2'. I want to draw a line graph of 'Headcount', which is the sum of the 2 series. However, when someone hovers on one data point, I want to show the individual values in the callout. Is this possible? How can I do this?
e.g.
H1 = (1, 2, 3)
H2 = (5, 6, 7)
Ht = (6, 8, 10)
I will draw a line graph with Ht. If I hover on '6' on the chart, the callout should show the values of H1 = 1 and H2 = 5

Answer 1

You can set the visibility for series H1 and H2 to false,
series: [{
name: 'H1',
data: [1, 2, 3],
visible: false,
showInLegend: false
}, {
name: 'H2',
data: [5, 6, 7],
visible: false,
showInLegend: false
}, {
name: 'H',
data: [6, 8, 10]
}]
and edit tooltip formatter to display what you want
tooltip: {
formatter: function() {
var s = '<b>' + this.x + '</b>';
var chart = this.points[0].series.chart; //get the chart object
var categories = chart.xAxis[0].categories; //get the categories array
var index = 0;
while(this.x !== categories[index]){index++;} //compute the index of corr y value in each data arrays
$.each(chart.series, function(i, series) { //loop through series array
if (series.name !== 'H') {
s += '<br/>'+ series.name +': ' +
series.data[index].y +'m'; //use index to get the y value
}
});
return s;
},
shared: true
}
Have a look at jsfiddle.net/s190ebby/27/

Answer 2

Yes
Points can have custom property, taking care that the names do not shadow highcharts variable names.
var data = [{
y: 6,
h1Value: 1,
h2Value: 5
},{
y: 8,
h1Value: 2,
h2Value: 6
}];
Set your series to this data in your config object, by series: data
Customise the tooltip as:
tooltip: {
pointFormat: '<b>H Value</b>: {point.y}<br/>
<b>H1 Value</b>: {point.h1Value}<br/>
<b>H2 Value</b>: {point.h2Value}'
}