Example:
/// Example of a time series chart with a confidence interval.
///
/// Confidence interval is defined by specifying the upper and lower measure
/// bounds in the series.
import 'package:community_charts_flutter/flutter.dart' as charts;
import 'package:flutter/material.dart';
class TimeSeriesConfidenceInterval extends StatelessWidget {
final List<charts.Series> seriesList;
final bool animate;
TimeSeriesConfidenceInterval(this.seriesList, {this.animate});
/// Creates a [TimeSeriesChart] with sample data and no transition.
factory TimeSeriesConfidenceInterval.withSampleData() {
return new TimeSeriesConfidenceInterval(
_createSampleData(),
// Disable animations for image tests.
animate: false,
);
}
@override
Widget build(BuildContext context) {
return new charts.TimeSeriesChart(
seriesList,
animate: animate,
// Optionally pass in a [DateTimeFactory] used by the chart. The factory
// should create the same type of [DateTime] as the data provided. If none
// specified, the default creates local date time.
dateTimeFactory: const charts.LocalDateTimeFactory(),
);
}
/// Create one series with sample hard coded data.
static List<charts.Series<TimeSeriesSales, DateTime>> _createSampleData() {
final data = [
new TimeSeriesSales(new DateTime(2017, 9, 19), 5),
new TimeSeriesSales(new DateTime(2017, 9, 26), 25),
new TimeSeriesSales(new DateTime(2017, 10, 3), 100),
new TimeSeriesSales(new DateTime(2017, 10, 10), 75),
];
return [
new charts.Series<TimeSeriesSales, DateTime>(
id: 'Sales',
colorFn: (_, __) => charts.MaterialPalette.blue.shadeDefault,
domainFn: (TimeSeriesSales sales, _) => sales.time,
measureFn: (TimeSeriesSales sales, _) => sales.sales,
// When the measureLowerBoundFn and measureUpperBoundFn is defined,
// the line renderer will render the area around the bounds.
measureLowerBoundFn: (TimeSeriesSales sales, _) => sales.sales - 5,
measureUpperBoundFn: (TimeSeriesSales sales, _) => sales.sales + 5,
data: data,
)
];
}
}
/// Sample time series data type.
class TimeSeriesSales {
final DateTime time;
final int sales;
TimeSeriesSales(this.time, this.sales);
}