transformValues method

@override void transformValues()

Transforms the x and y values to screen coordinates.

Implementation

@override
void transformValues() {
  if (xValue.isNaN || high.isNaN || low.isNaN) {
    return;
  }

  points.clear();

  final PointToPixelCallback transformX = series.pointToPixelX;
  final PointToPixelCallback transformY = series.pointToPixelY;

  final double centerY = (low + high) / 2;
  if (high == low) {
    if (series.showIndicationForSameValues) {
      if (series.isTransposed) {
        points.add(
          Offset(transformX(xValue, high) - 2, transformY(xValue, high)),
        );
        points.add(
          Offset(transformX(xValue, low) + 2, transformY(xValue, low)),
        );
      } else {
        points.add(
          Offset(transformX(xValue, high), transformY(xValue, high) - 2),
        );
        points.add(
          Offset(transformX(xValue, low), transformY(xValue, low) + 2),
        );
      }
    }
  } else {
    points.add(Offset(transformX(xValue, high), transformY(xValue, high)));
    points.add(Offset(transformX(xValue, low), transformY(xValue, low)));
  }

  if (_oldPoints.isEmpty) {
    final Offset center = Offset(
      transformX(xValue, centerY),
      transformY(xValue, centerY),
    );
    _oldPoints.addAll(<Offset>[center, center]);
  }

  if (points.length > _oldPoints.length) {
    _oldPoints.addAll(points.sublist(_oldPoints.length));
  }
}