charts
Gauge Pie Chart Example
Example:
/// Gauge chart example, where the data does not cover a full revolution in the
/// chart.
import 'package:charts_flutter/flutter.dart' as charts;
import 'package:flutter/material.dart';
class GaugeChart extends StatelessWidget {
final List<charts.Series> seriesList;
final bool animate;
GaugeChart(this.seriesList, {this.animate});
/// Creates a [PieChart] with sample data and no transition.
factory GaugeChart.withSampleData() {
return new GaugeChart(
_createSampleData(),
// Disable animations for image tests.
animate: false,
);
}
@override
Widget build(BuildContext context) {
return new charts.PieChart(seriesList,
animate: animate,
// Configure the width of the pie slices to 30px. The remaining space in
// the chart will be left as a hole in the center. Adjust the start
// angle and the arc length of the pie so it resembles a gauge.
defaultRenderer: new charts.ArcRendererConfig(
arcWidth: 30, startAngle: 4 / 5 * pi, arcLength: 7 / 5 * pi));
}
/// Create one series with sample hard coded data.
static List<charts.Series<GaugeSegment, String>> _createSampleData() {
final data = [
new GaugeSegment('Low', 75),
new GaugeSegment('Acceptable', 100),
new GaugeSegment('High', 50),
new GaugeSegment('Highly Unusual', 5),
];
return [
new charts.Series<GaugeSegment, String>(
id: 'Segments',
domainFn: (GaugeSegment segment, _) => segment.segment,
measureFn: (GaugeSegment segment, _) => segment.size,
data: data,
)
];
}
}
/// Sample data type.
class GaugeSegment {
final String segment;
final int size;
GaugeSegment(this.segment, this.size);
}