Update bar_secondary_axis.md

docs/flutter/example/axes/bar_secondary_axis.md

@@ -6,6 +6,7 @@ Example:
 
 ```
 /// Bar chart example
+
 import 'package:flutter/material.dart';
 import 'package:charts_flutter/flutter.dart' as charts;
 
@@ -22,7 +23,9 @@ import 'package:charts_flutter/flutter.dart' as charts;
 /// secondaryMeasureAxisId.
 ///
 /// Note: primary and secondary may flip left and right positioning when
+
 /// RTL.flipAxisLocations is set.
+
 class BarChartWithSecondaryAxis extends StatelessWidget {
   static const secondaryMeasureAxisId = 'secondaryMeasureAxisId';
   final List<charts.Series> seriesList;
@@ -43,11 +46,12 @@ class BarChartWithSecondaryAxis extends StatelessWidget {
   Widget build(BuildContext context) {
     return new charts.BarChart(
       seriesList,
-      animate: animate,
+      animate: animate, 
       barGroupingType: charts.BarGroupingType.grouped,
       // It is important when using both primary and secondary axes to choose
       // the same number of ticks for both sides to get the gridlines to line
       // up.
+
       primaryMeasureAxis: new charts.NumericAxisSpec(
           tickProviderSpec:
               new charts.BasicNumericTickProviderSpec(desiredTickCount: 3)),
@@ -60,17 +64,17 @@ class BarChartWithSecondaryAxis extends StatelessWidget {
   /// Create series list with multiple series
   static List<charts.Series<OrdinalSales, String>> _createSampleData() {
     final globalSalesData = [
-      new OrdinalSales('2014', 5000),
-      new OrdinalSales('2015', 25000),
-      new OrdinalSales('2016', 100000),
-      new OrdinalSales('2017', 750000),
+       OrdinalSales('2014', 5000),
+       OrdinalSales('2015', 25000),
+       OrdinalSales('2016', 100000),
+       OrdinalSales('2017', 750000),
     ];
 
     final losAngelesSalesData = [
-      new OrdinalSales('2014', 25),
-      new OrdinalSales('2015', 50),
-      new OrdinalSales('2016', 10),
-      new OrdinalSales('2017', 20),
+       OrdinalSales('2014', 25),
+       OrdinalSales('2015', 50),
+       OrdinalSales('2016', 10),
+       OrdinalSales('2017', 20),
     ];
 
     return [
@@ -86,14 +90,17 @@ class BarChartWithSecondaryAxis extends StatelessWidget {
         measureFn: (OrdinalSales sales, _) => sales.sales,
         data: losAngelesSalesData,
       )..setAttribute(charts.measureAxisIdKey, secondaryMeasureAxisId)
+
       // Set the 'Los Angeles Revenue' series to use the secondary measure axis.
       // All series that have this set will use the secondary measure axis.
       // All other series will use the primary measure axis.
+
     ];
   }
 }
 
 /// Sample ordinal data type.
+
 class OrdinalSales {
   final String year;
   final int sales;