Did x axis and y axis sort?

Hi I create a line chart but I could not let the x axis and y axis sort same time.

if I sort the data for y axis, the graph will show ...

my line chart code...

LineChart(
            chartPadding: new EdgeInsets.fromLTRB(50, 35, 50, 35),
            lines: [
              new Line<FuelListDetailList, String, double>(
                data: consumption,
                xFn: (list) => list.record_date,
                yFn: (list) => list.liters_per_km,
                xAxis: xAxis,
                yAxis: new ChartAxis(
                  tickLabelerStyle: new TextStyle(
                      color: Colors.blue, fontWeight: FontWeight.bold),
                  paint: const PaintOptions.stroke(color: Colors.blue),
                ),
                marker: const MarkerOptions(
                  paint: const PaintOptions.fill(color: Colors.blue),
                ),
                stroke: const PaintOptions.stroke(color: Colors.blue),
                legend: new LegendItem(
                  paint: const PaintOptions.fill(color: Colors.blue),
                  text: ")",
                ),
              ),

              // price line
              new Line<FuelListDetailList, String, double>(
                data: price,
                xFn: (list) => list.record_date,
                yFn: (list) => list.total_price,
                xAxis: xAxis,
                yAxis: new ChartAxis(
                  opposite: true,
                  paint: const PaintOptions.stroke(color: Colors.green),
                  tickLabelerStyle: new TextStyle(
                      color: Colors.green, fontWeight: FontWeight.bold),
                ),
                marker: const MarkerOptions(
                  paint: const PaintOptions.fill(color: Colors.green),
                  shape: MarkerShapes.square,
                ),
                stroke: const PaintOptions.stroke(color: Colors.green),
                legend: new LegendItem(
                  paint: const PaintOptions.fill(color: Colors.green),
                  text: 'price',
                ),
              ),
            ],
          ),

or can I fixed the y axis value like this...?

thekeenant / fcharts

Did x axis and y axis sort? #39