flutterchartssyncfusionsfcartesianchart

In the Syncfusion chart with Flutter, the lines are added on the previous value


Plotting each series with reference to zero.

The second series is added on the first series value.

chart

datas

The first series is drawn correctly as 10-10-10. The second series should start from 0 as 0-5-10. But it starts at 10. It's drawn as 10-15-20.

How do I make the second series reference 0?

SfCartesianChart _buildStackedLineChart() {
    return SfCartesianChart(
      plotAreaBorderWidth: 0,
      backgroundColor: Colors.white,
      title: ChartTitle(text: 'Temperature', textStyle: TextStyle()),
      legend: const Legend(
        isVisible: true,
        position: LegendPosition.top,
        itemPadding: 25,
        padding: 5,
      ),
      primaryXAxis: DateTimeAxis(
        majorGridLines: const MajorGridLines(width: 0),
        dateFormat: DateFormat.H(), 
        intervalType: DateTimeIntervalType.hours, 
      ),
      primaryYAxis: const NumericAxis(
          axisLine: AxisLine(width: 0),
          labelFormat: '{value}°C', 
          majorGridLines: MajorGridLines(width: 0),
          minimum: 0,
        ),
      series: _getStackedLineSeries(),
      trackballBehavior: _trackballBehavior,
    );
  }

https://gist.github.com/MucahitZengin/4bc25cec2a26f10af9cf5c84a9db4c39

https://flutter.syncfusion.com/#/cartesian-charts/chart-types/stacked-charts/stacked-line-chart

https://github.com/syncfusion/flutter-examples/blob/master/lib/samples/chart/cartesian_charts/chart_types/stacked_charts/stacked_line_chart.dart


Solution

  • I think I understand the source of the problem. I am using a "stacked line chart". In a stacked line chart the data is stacked. I should use the "default line chart".

    Like this one here:

    https://flutter.syncfusion.com/#/cartesian-charts/chart-types/line/default-line-chart

    The source of the solution:

    https://github.com/syncfusion/flutter-examples/issues/115

    Thank you: SriramKiranSenthilkumar