trackballInfo method
Implementation
@override
TrackballInfo? trackballInfo(Offset position, int pointIndex) {
if (pointIndex != -1 && segmentRect != null) {
final CartesianChartPoint<D> chartPoint = _chartPoint();
return ChartTrackballInfo<T, D>(
position: segmentRect!.center,
point: chartPoint,
series: series,
seriesIndex: series.index,
segmentIndex: currentSegmentIndex,
pointIndex: currentSegmentIndex,
text: series.trackballText(chartPoint, series.name),
header: series.tooltipHeaderText(chartPoint),
color: fillPaint.color,
);
}
return null;
}