Basic pie chart

[AlexanderBrese]

Code

import 'package:charts_flutter/flutter.dart' as charts;
import 'package:flutter/material.dart';

class BarCounter {
  final int domain;
  final int measure;
  final charts.Color color;

  BarCounter(this.domain, this.measure, Color color)
      : this.color = new charts.Color(
            r: color.red, g: color.green, b: color.blue, a: color.alpha);
}

class Statistics {
  Statistics(
      this.trackAmount,
      this.barAmount,
      this.lastTrackDate,
      this.barCounters,
      this.tracksMonthly,
      this.tracksDaily,
      this.speedCounters);

  int trackAmount;
  int barAmount;
  DateTime lastTrackDate;
  List<BarCounter> barCounters;
  List<int> tracksMonthly;
  List<int> tracksDaily;
  List<int> speedCounters;
}

class BarCounterChart extends StatelessWidget {
  final List<charts.Series> seriesList;
  final bool animate;

  BarCounterChart(List<BarCounter> barCounters, {this.animate})
      : this.seriesList = [
          new charts.Series<BarCounter, int>(
            id: 'BarCounter',
            domainFn: (BarCounter barCounter, _) => barCounter.domain,
            measureFn: (BarCounter barCounter, _) => barCounter.measure,
            colorFn: (BarCounter barCounter, _) => barCounter.color,
            data: barCounters,
          ),
        ];

  @override
  Widget build(BuildContext context) {
    return new charts.PieChart<BarCounter, int>(seriesList, animate: animate);
  }
}

pubspec.yaml

dependencies:
  flutter:
    sdk: flutter
  cupertino_icons: ^0.1.0
  intl: ^0.15.6
  charts_flutter: ^0.2.0
  timeago: ^1.2.1
  flutter_gallery_assets:
      git:
        url: https://flutter.googlesource.com/gallery-assets
        ref: d318485f208376e06d7e330d9f191141d14722b8

Error message

Another exception was thrown: type '(BarCounter, int) => int' is not a subtype of type '(dynamic, int) => dynamic'

[rsnider19]

I am getting this same error after upgrading to Dart 2. I Think it has to do with Dart 2's strong mode for typing.

[lorrainekan]

You just need

new charts.PieChart<BarCounter>(...

In an upcoming release, you should only need new charts.PieChart(... since we removed the generic from the chart itself.