Example:
/// Example of a percentage bar chart which shows each bar as the percentage of
/// the total series measure value.
import 'package:flutter/material.dart';
import 'package:charts_flutter/flutter.dart' as charts;
class PercentOfSeriesBarChart extends StatelessWidget {
final List<charts.Series> seriesList;
final bool animate;
PercentOfSeriesBarChart(this.seriesList, {this.animate});
/// Creates a stacked [BarChart] with sample data and no transition.
factory PercentOfSeriesBarChart.withSampleData() {
return new PercentOfSeriesBarChart(
_createSampleData(),
// Disable animations for image tests.
animate: false,
);
}
@override
Widget build(BuildContext context) {
return new charts.BarChart(
seriesList,
animate: animate,
barGroupingType: charts.BarGroupingType.grouped,
// Configures a [PercentInjector] behavior that will calculate measure
// values as the percentage of the total of all data in its series.
behaviors: [
new charts.PercentInjector(
totalType: charts.PercentInjectorTotalType.series)
],
// Configure the axis spec to show percentage values.
primaryMeasureAxis: new charts.PercentAxisSpec(),
);
}
/// Create series list with multiple series
static List<charts.Series<OrdinalSales, String>> _createSampleData() {
final desktopSalesData = [
new OrdinalSales('2011', 5),
new OrdinalSales('2012', 25),
new OrdinalSales('2013', 50),
new OrdinalSales('2014', 75),
new OrdinalSales('2015', 100),
new OrdinalSales('2016', 125),
new OrdinalSales('2017', 200),
new OrdinalSales('2018', 150),
];
return [
new charts.Series<OrdinalSales, String>(
id: 'Desktop',
domainFn: (OrdinalSales sales, _) => sales.year,
measureFn: (OrdinalSales sales, _) => sales.sales,
data: desktopSalesData,
),
];
}
}
/// Sample ordinal data type.
class OrdinalSales {
final String year;
final int sales;
OrdinalSales(this.year, this.sales);
}