How do i get date and time in points highchart? - php

Question

I plot highcharts on my page.
This works great but i have one little problem that in my points when i hover with my mouse on it, i get no date and time with it.
This is what my json is like.:
[{"metingen":"metingen","Datum":"Datum","data":["5-9-2022",14.6,"5-9-2022",14.8,"6-9-2022",15.948,"6-9-2022",17.112,"6-9-2022",
My chart look then like this.:
You see on the left the baloon, it show the number 0: 14.6.
14.6 is the value, thats good but the 0 is number of that value sutch as another point, that gives
But how can i show the date and time thats belong with that number in the baloon?
My chart code is this.:
$.getJSON("mfrmetingen300RG.json", function(data) {
const processedData9 = [];
for (let a = 0; a < data[0].data.length; a += 2) {
processedData9.push([data[0].data[a], data[0].data[a + 1]]);
}
data[0].data = processedData9;
avg = <?php echo $rowj[0]; ?>;
StDev = <?php echo $rowj[1]; ?>;
Aantalwaarden9 = <?php echo $rowj[2]; ?>;
//Cp=(USL-LSL)/(6xstd.Dev) see.:https://www.easycalculation.com/statistics/learn-cp-cpk-calculator.php
//Cpk = (USL-gemiddelde) / (3 x std.Dev) of (gemiddelde-LSL) / (3 x std.Dev)
cpkl1 = (<?php echo $_cpkh10waarde; ?>-<?php echo $_cpkl10waarde; ?>)/(6*StDev);
Cpk1High = (<?php echo $_cpkh10waarde; ?>-avg)/(3*StDev);
Cpk1Low = (avg-<?php echo $_cpkl10waarde; ?>)/(3*StDev);
chart9 = new Highcharts.Chart('container9',{
chart: {
zoomType: 'x',
type: 'line',
marginRight: 130,
marginBottom: 100,
backgroundColor:'azure'
},
rangeSelector: {
buttons: [{
text: '+',
events: {
click() {
return false
}
}
},
{
text: '-',
events: {
click() {
return false
}
}
}]
},
title: {
useHTML: true,
text: "Gemeten MFR waarde van PP 300R Grey Extrusie over de laatste "+(Aantalwaarden9)+" waarden.",
x: -20 //center
},
credits: {
enabled: false
},
subtitle: {text: 'Gem.='+avg.toFixed(2)+' Stdev='+StDev.toFixed(2)+' Cp='+cpkl1.toFixed(2)+' Cpk_High='+Cpk1High.toFixed(2)+' Cpk_Low='+Cpk1Low.toFixed(2)+'',x: -20},
xAxis: {
uniqueNames: false,
type: 'category',
title: {
text: 'Datum'
}
},
yAxis: {
"min":15,
"max":23,
title: {
text: 'MFR'
},
plotLines: [{
value: 0,
width: 1,
color: '#808080'
}],
plotLines: [{value: <?php echo $_cpkl10waarde; ?>,color: <?php echo $_color_min_line; ?>,dashStyle: 'longdashdot',width: 2,label: {text: 'Minimum'}},
{value: <?php echo $_cpkh10waarde; ?>,color: <?php echo $_color_max_line; ?>,dashStyle: 'longdashdot',width: 2,label: {text: 'Maximum'}},
{value: <?php echo $_cpkm10waarde; ?>,color: <?php echo $_color_guide_line; ?>,dashStyle: 'shortdash',width: 2,label: {text: 'Richtlijn'}},
{value: avg.toFixed(2),color: <?php echo $_color_avg_line; ?>,dashStyle: 'spline',width: 2,label: {text: 'Avg'}},
]
},
tooltip: {
formatter: function() {
return '<b>Meetwaarden</b><br/>'+ this.x +': '+ this.y;
}
},
legend: {layout: 'vertical',align: 'right',verticalAlign: 'top', x: -100,y: 0,floating: true,borderWidth: 0},
series: data,
plotOptions: {
line: {
dataLabels: {
enabled: true
}
}
},
});
chart9.legend.allItems[0].update({name:'MFR'});
}, 1000);
});```

Answer 1

Because you have category type xAxis, your category name is contained in point.key variable. So, based on your example, you only need to refer to this.key
tooltip: {
formatter: function() {
return '<b>Meetwaarden</b><br/>'+ this.key +': '+ this.y;
}
},
Simplified Demo:
https://jsfiddle.net/BlackLabel/87bousnL/
API Reference:
https://api.highcharts.com/highcharts/tooltip.headerFormat