contains method

@override List<ChartSegment> contains(Offset position)

Implementation

@override
List<ChartSegment> contains(Offset position) {
  if (animationController != null && animationController!.isAnimating) {
    return <ChartSegment>[];
  }
  final List<ChartSegment> segmentCollection = <ChartSegment>[];
  int index = 0;
  double delta = 0;
  num? nearPointX;
  num? nearPointY;
  for (final ChartSegment segment in segments) {
    if (segment is LineSegment<T, D>) {
      nearPointX ??= segment.series.xValues[0];
      nearPointY ??= segment.series.yAxis!.visibleRange!.minimum;
      final Rect rect = segment.series.paintBounds;

      final num touchXValue =
          segment.series.xAxis!.pixelToPoint(rect, position.dx, position.dy);
      final num touchYValue =
          segment.series.yAxis!.pixelToPoint(rect, position.dx, position.dy);
      final double curX = segment.series.xValues[index].toDouble();
      final double curY = segment.series.yValues[index].toDouble();
      if (delta == touchXValue - curX) {
        if ((touchYValue - curY).abs() > (touchYValue - nearPointY).abs()) {
          segmentCollection.clear();
        }
        segmentCollection.add(segment);
      } else if ((touchXValue - curX).abs() <=
          (touchXValue - nearPointX).abs()) {
        nearPointX = curX;
        nearPointY = curY;
        delta = touchXValue - curX;
        segmentCollection.clear();
        segmentCollection.add(segment);
      }
    }
    index++;
  }
  return segmentCollection;
}