tooltipInfo method

@override TooltipInfo? tooltipInfo({ Offset? position, int? pointIndex, })

Implementation

@override
TooltipInfo? tooltipInfo({Offset? position, int? pointIndex}) {
  if (points.isEmpty) {
    return null;
  }

  pointIndex ??= _findNearestChartPointIndex(points, position!);
  if (pointIndex != -1) {
    final Offset position = points[pointIndex];
    if (position.isNaN) {
      return null;
    }

    final int actualPointIndex = _drawIndexes[pointIndex];
    final CartesianChartPoint<D> chartPoint = _chartPoint(actualPointIndex);
    final num x = chartPoint.xValue!;
    final num y = series.topValues[actualPointIndex];
    final double dx = series.pointToPixelX(x, y);
    final double dy = series.pointToPixelY(x, y);
    final ChartMarker marker = series.markerAt(pointIndex);
    final double markerHeight =
        series.markerSettings.isVisible ? marker.height / 2 : 0;
    final Offset preferredPos = Offset(dx, dy);
    return ChartTooltipInfo<T, D>(
      primaryPosition:
          series.localToGlobal(preferredPos.translate(0, -markerHeight)),
      secondaryPosition:
          series.localToGlobal(preferredPos.translate(0, markerHeight)),
      text: series.tooltipText(chartPoint),
      header: series.parent!.tooltipBehavior!.shared
          ? series.tooltipHeaderText(chartPoint)
          : series.name,
      data: series.dataSource![pointIndex],
      point: chartPoint,
      series: series.widget,
      renderer: series,
      seriesIndex: series.index,
      segmentIndex: currentSegmentIndex,
      pointIndex: actualPointIndex,
      markerColors: <Color?>[fillPaint.color],
      markerType: marker.type,
    );
  }
  return null;
}