I've been grappling with getting tooltips to work in amCharts4 when using a DurationAxis(). It seems like there might be a bug, as the tooltips sometimes get stuck in the top left corner.
Here's an example: https://jsfiddle.net/jamiegau/fpye3bkv/25/
am4core.useTheme(am4themes_animated);
// Creating the chart
var chart = am4core.create("chartdiv", am4charts.XYChart);
// Adding data
chart.data = [{
"seconds": 1,
"valueM": 12.1
}, {
"seconds": 2,
"valueM": 4.2
}, {
"seconds": 4,
"valueM": 7.3
}, {
"seconds": 6,
"valueM": 8.4
}, {
"seconds": 9,
"valueM": 4.5
}, {
"seconds": 104,
"valueM": 10.7
}];
var durationAxis = chart.xAxes.push(new am4charts.DurationAxis());
durationAxis.baseUnit = 'second';
durationAxis.title.text = 'Duration';
var valueAxis = chart.yAxes.push(new am4charts.ValueAxis());
// Adding cursor
chart.cursor = new am4charts.XYCursor();
var series = chart.series.push(new am4charts.LineSeries());
series.dataFields.valueY = 'valueM';
series.dataFields.valueX = 'seconds';
series.yAxis = valueAxis;
series.name = 'Momentary';
series.strokeWidth = 2;
series.minBulletDistance = 10;
series.tooltipText = 'M: {valueY}';
I've used similar code with a DateAxis() without any issues. However, when trying it with a DurationAxis(), things start going wrong with tooltips.
In my actual code, I have 4 different series. But even when testing with just 1 series, I can't seem to solve it. I've tried everything, including reverting back to DateAxis, but it doesn't work for me because I need sub-second accuracy and the rounding on DateAxes looks terrible.
Update
This issue persists with both valueAxis and DurationAxis. After further investigation, it seems that having POINT tooltips on these types of axes is not supported by amCharts.
If I'm mistaken, please let me know.