show method

void show(dynamic x, double y, [ String coordinateUnit = 'point' ])

Displays the crosshair at the specified x and y-positions.

x & y - x and y values/pixel where the crosshair needs to be shown.

coordinateUnit - specify the type of x and y values given.'pixel' or 'point' for logica pixel and chart data point respectively. Defaults to 'point'.

Implementation

void show(dynamic x, double y, [String coordinateUnit = 'point']) {
  final SfCartesianChartState chartState = _chartState!;
  final CrosshairBehaviorRenderer crosshairBehaviorRenderer =
      chartState._crosshairBehaviorRenderer;
  if (coordinateUnit != 'pixel') {
    final CartesianSeriesRenderer seriesRenderer = crosshairBehaviorRenderer
        ._crosshairPainter!.chartState._chartSeries.visibleSeriesRenderers[0];
    final ChartAxisRenderer xAxisRenderer = seriesRenderer._xAxisRenderer!;
    final _ChartLocation location = _calculatePoint(
        (x is DateTime && xAxisRenderer is! DateTimeCategoryAxisRenderer)
            ? x.millisecondsSinceEpoch
            : ((x is DateTime &&
                    xAxisRenderer is DateTimeCategoryAxisRenderer)
                ? xAxisRenderer._labels
                    .indexOf(xAxisRenderer._dateFormat.format(x))
                : ((x is String && xAxisRenderer is CategoryAxisRenderer)
                    ? xAxisRenderer._labels.indexOf(x)
                    : x)),
        y,
        xAxisRenderer,
        seriesRenderer._yAxisRenderer!,
        seriesRenderer._chartState!._requireInvertedAxis,
        seriesRenderer._series,
        seriesRenderer._chartState!._chartAxis._axisClipRect);
    x = location.x;
    y = location.y.truncateToDouble();
  }

  if (crosshairBehaviorRenderer._crosshairPainter != null &&
      activationMode != ActivationMode.none &&
      x != null) {
    crosshairBehaviorRenderer._crosshairPainter!
        ._generateAllPoints(Offset(x.toDouble(), y));
    crosshairBehaviorRenderer._crosshairPainter!.canResetPath = false;
    crosshairBehaviorRenderer
        ._crosshairPainter!.chartState._crosshairRepaintNotifier.value++;
  }
}