Change X-axis Line Chart flutter

Question

I want to draw a line chart in flutter. I follow this tutorial, it works fine if the date and month is different.

But why if it only has one date and one point, the

Answer 1

With just one point the X axis has no scale, so it zooms in showing the single date in as much resolution as it can - in this case down to the nearest minute. That's midnight ("12AM") on the twelfth of March. To force a fixed scale use a StaticDateTimeTickProviderSpec. For example:

return Scaffold(
  appBar: AppBar(
    title: Text('Graph'),
  ),
  body: Container(
    height: 500,
    width: double.infinity,
    child: charts.TimeSeriesChart(
      _createSampleData(seriesList),
      domainAxis: charts.DateTimeAxisSpec(
        tickProviderSpec: charts.StaticDateTimeTickProviderSpec(
        <charts.TickSpec<DateTime>>[
          charts.TickSpec<DateTime>(DateTime(2020, 3, 1)),
          charts.TickSpec<DateTime>(DateTime(2020, 3, 6)),
          charts.TickSpec<DateTime>(DateTime(2020, 3, 11)),
          charts.TickSpec<DateTime>(DateTime(2020, 3, 16)),
          charts.TickSpec<DateTime>(DateTime(2020, 3, 21)),
          charts.TickSpec<DateTime>(DateTime(2020, 3, 26)),
          charts.TickSpec<DateTime>(DateTime(2020, 4, 1)),
        ],
      ),
        tickFormatterSpec: charts.AutoDateTimeTickFormatterSpec(
          day: charts.TimeFormatterSpec(
            format: 'dd MMM',
            transitionFormat: 'dd MMM',
          ),
        ),
      ),
      animate: false,
      behaviors: [
        charts.SlidingViewport(),
        charts.PanAndZoomBehavior(),
      ],
      dateTimeFactory: const charts.LocalDateTimeFactory(),
      defaultRenderer: charts.LineRendererConfig(
        includePoints: true,
      ),
    ),
  ),
);