Chart memory leak example

chart_memory_leak.dart

// Flutter code sample for Scaffold

// This example shows a [Scaffold] with an [AppBar], a [BottomAppBar] and a
// [FloatingActionButton]. The [body] is a [Text] placed in a [Center] in order
// to center the text within the [Scaffold]. The [FloatingActionButton] is
// centered and docked within the [BottomAppBar] using
// [FloatingActionButtonLocation.centerDocked]. The [FloatingActionButton] is
// connected to a callback that increments a counter.
//
// ![](https://flutter.github.io/assets-for-api-docs/assets/material/scaffold_bottom_app_bar.png)

import 'package:flutter/material.dart';

import 'patched/syncfusion_flutter_charts/lib/charts.dart';

void main() => runApp(MyApp());

/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: MyStatefulWidget(),
    );
  }
}

class MyStatefulWidget extends StatefulWidget {
  MyStatefulWidget({Key key}) : super(key: key);

  @override
  _MyStatefulWidgetState createState() => _MyStatefulWidgetState();
}

class DataPoint {
  int end;
  DateTime date;
}

class _MyStatefulWidgetState extends State<MyStatefulWidget> {
  int _count = 0;
  final myData = [
    DataPoint()
      ..date = DateTime(2020, 01, 01)
      ..end = 0,
    DataPoint()
      ..date = DateTime(2020, 01, 02)
      ..end = 100,
  ];

  Widget build(BuildContext context) {
    final chartKey = Key('chartKey');
    return Scaffold(
      appBar: AppBar(
        title: Text('Sample Code'),
      ),
      body: Center(
        child: Column(
          children: <Widget>[
            Text('You have pressed the button $_count times.'),
            SfCartesianChart(
              // Uncomment to force dispose on rebuild and stop memory leak
              // key: UniqueKey(),
              primaryXAxis: DateTimeAxis(),
              primaryYAxis: NumericAxis(),
              key: chartKey,
              series: <ChartSeries>[
                SplineSeries<DataPoint, DateTime>(
                  animationDuration: 0,
                  width: 1,
                  splineType: SplineType.monotonic,
                  dataSource: myData,
                  xValueMapper: (DataPoint s, _) => s.date,
                  yValueMapper: (DataPoint s, _) => s.end,
                )
              ],
            )
          ],
        ),
      ),
      bottomNavigationBar: BottomAppBar(
        shape: const CircularNotchedRectangle(),
        child: Container(
          height: 50.0,
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () => setState(() {
          _count++;
        }),
        tooltip: 'Increment Counter',
        child: Icon(Icons.add),
      ),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
    );
  }
}