stock_market_data 0.1.4

Package to get base indicators from the stock and base stats like buy and hold CAGR and total drawdown

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:stock_market_data/stock_market_data.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  ThemeMode _themeMode = ThemeMode.light;

  void _toggleTheme() {
    setState(() {
      _themeMode = _themeMode == ThemeMode.light
          ? ThemeMode.dark
          : ThemeMode.light;
    });
  }

  @override
  Widget build(BuildContext context) => MaterialApp(
    title: 'Flutter Demo',
    themeMode: _themeMode,
    debugShowCheckedModeBanner: false,
    theme: ThemeData.light(),
    darkTheme: ThemeData.dark(),
    home: HomeScreen(onToggleTheme: _toggleTheme),
  );
}

class HomeScreen extends StatelessWidget {
  final VoidCallback onToggleTheme;

  const HomeScreen({required this.onToggleTheme, super.key});

  @override
  Widget build(BuildContext context) => Scaffold(
    appBar: AppBar(
      title: const Text('Stock Market Example'),
      actions: [
        IconButton(
          icon: const Icon(Icons.brightness_6),
          onPressed: onToggleTheme,
        ),
      ],
    ),
    body: Container(
      padding: const EdgeInsets.all(20),
      child: const SingleChildScrollView(
        child: Column(
          children: [
            SizedBox(
              height: 355,
              width: double.infinity,
              child: BuyAndHoldResult(exampleTicker: 'AAPL'),
            ),
            SizedBox(
              height: 355,
              width: double.infinity,
              child: BuyAndHoldResult(exampleTicker: 'VUSA.AS'),
            ),
            SizedBox(
              height: 355,
              width: double.infinity,
              child: BuyAndHoldResult(exampleTicker: 'ES=F, GC=F'),
            ),
          ],
        ),
      ),
    ),
  );
}

class BuyAndHoldResult extends StatefulWidget {
  final String exampleTicker;

  const BuyAndHoldResult({required this.exampleTicker, super.key});

  @override
  State<BuyAndHoldResult> createState() => _BuyAndHoldResultState();
}

class _BuyAndHoldResultState extends State<BuyAndHoldResult> {
  final TextEditingController controller = TextEditingController();
  BuyAndHoldStrategyResult backTest = BuyAndHoldStrategyResult();
  bool loading = true;
  String error = '';

  @override
  void initState() {
    super.initState();
    controller.text = widget.exampleTicker;
    load();
  }

  @override
  Widget build(BuildContext context) => Column(
    children: [
      const Text('Ticker from yahoo finance'),
      TextField(controller: controller),
      MaterialButton(
        onPressed: load,
        color: Theme.of(context).primaryColor,
        child: const Text('Load'),
      ),
      Expanded(
        child: error.isNotEmpty
            ? Text('Error: $error')
            : loading
            ? const Center(child: CircularProgressIndicator())
            : ListView(
                padding: const EdgeInsets.all(8),
                children: [
                  const SizedBox(height: 20),
                  _BackTestResult(backTest),
                  const SizedBox(height: 20),
                  Row(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      MaterialButton(
                        onPressed: () => Navigator.of(context).push(
                          MaterialPageRoute(
                            builder: (context) =>
                                _IndicatorsData(controller.text),
                          ),
                        ),
                        color: Colors.teal,
                        child: const Text('Indicators'),
                      ),
                      const SizedBox(width: 20),
                      MaterialButton(
                        onPressed: () => Navigator.of(context).push(
                          MaterialPageRoute(
                            builder: (context) =>
                                _YearStatsWidget(controller.text),
                          ),
                        ),
                        color: Colors.orange,
                        child: const Text('Year stats'),
                      ),
                    ],
                  ),
                ],
              ),
      ),
    ],
  );

  Future<void> load() async {
    try {
      setState(() {
        error = '';
        loading = true;
      });

      backTest = await StockMarketDataService().getBackTestResultForSymbol(
        controller.text,
      );

      setState(() => loading = false);
    } catch (e) {
      setState(() {
        error = 'Error getting the symbol ${controller.text}:\n $e';
        loading = false;
      });
    }
  }
}

class _BackTestResult extends StatelessWidget {
  final BuyAndHoldStrategyResult backTest;

  const _BackTestResult(this.backTest);

  @override
  Widget build(BuildContext context) => Column(
    children: [
      _row('CAGR', backTest.cagr.toStringAsFixed(2)),
      _row('Max Drawdown', backTest.maxDrawdown.toStringAsFixed(2)),
      _row('MAR', backTest.mar.toStringAsFixed(2)),
      _row('Trading years', backTest.tradingYears.toStringAsFixed(2)),
      _row('Start date', backTest.startDate.toString()),
      _row('End date', backTest.endDate.toString()),
      _row('Current drawdown', backTest.currentDrawdown.toStringAsFixed(2)),
      _row('End price', backTest.endPrice.toStringAsFixed(2)),
    ],
  );

  Widget _row(String label, String value) => Row(
    children: [
      Expanded(child: Text(label)),
      Expanded(child: Text(value)),
    ],
  );
}

class _YearStatsWidget extends StatefulWidget {
  final String symbol;

  const _YearStatsWidget(this.symbol);

  @override
  State<_YearStatsWidget> createState() => _YearStatsWidgetState();
}

class _YearStatsWidgetState extends State<_YearStatsWidget> {
  List<YahooFinanceCandleData> prices = [];
  List<YearlyStats> yearlyStats = [];

  @override
  void initState() {
    super.initState();
    load();
  }

  Future<void> load() async {
    final YahooFinanceResponse response = await const YahooFinanceDailyReader()
        .getDailyDTOs(widget.symbol);

    prices = response.candlesData;
    yearlyStats = YearlyCalculations.calculate(prices);

    setState(() {});
  }

  @override
  Widget build(BuildContext context) => Scaffold(
    appBar: AppBar(title: const Text('Year stats')),
    body: Column(
      children: [
        const Row(
          children: [
            Expanded(child: Text('Year')),
            Expanded(child: Text('Variation')),
            Expanded(child: Text('Drawdown')),
          ],
        ),
        const SizedBox(height: 10),
        Expanded(
          child: ListView.builder(
            itemCount: yearlyStats.length,
            itemBuilder: (context, index) {
              final y = yearlyStats[index];
              return Row(
                children: [
                  Expanded(child: Text(y.year.toString())),
                  Expanded(child: Text(y.variation.toStringAsFixed(2))),
                  Expanded(child: Text(y.drawdown.toStringAsFixed(2))),
                ],
              );
            },
          ),
        ),
      ],
    ),
  );
}

class _IndicatorsData extends StatefulWidget {
  final String symbol;

  const _IndicatorsData(this.symbol);

  @override
  State<_IndicatorsData> createState() => _IndicatorsDataState();
}

class _IndicatorsDataState extends State<_IndicatorsData> {
  final TextEditingController indicatorsController = TextEditingController(
    text:
        'SMA_20,EMA_20,RSI_20,STDDEV_20,VWMA_20,BB_20,%R_20,MFI_14,BOP_14,P_1',
  );

  List<YahooFinanceCandleData> prices = [];

  Future<void> load() async {
    prices = await StockMarketDataService().getCandlesWithIndicators(
      widget.symbol,
      indicatorsController.text.split(','),
    );

    prices = prices.reversed.toList();
    setState(() {});
  }

  @override
  Widget build(BuildContext context) => Scaffold(
    appBar: AppBar(title: const Text('Indicators')),
    body: ListView.builder(
      itemCount: prices.length + 1,
      itemBuilder: (context, index) {
        if (index == 0) {
          return Container(
            margin: const EdgeInsets.all(10),
            child: Column(
              children: [
                const Text('Indicators'),
                TextField(controller: indicatorsController, maxLines: 3),
                MaterialButton(
                  onPressed: load,
                  color: Theme.of(context).primaryColor,
                  child: const Text('Load'),
                ),
              ],
            ),
          );
        }

        final candle = prices[index - 1];
        return _PriceWithIndicators(candle);
      },
    ),
  );
}

class _PriceWithIndicators extends StatelessWidget {
  final YahooFinanceCandleData candle;

  const _PriceWithIndicators(this.candle);

  @override
  Widget build(BuildContext context) => Card(
    child: Container(
      margin: const EdgeInsets.all(10),
      child: Column(
        children: [
          Text('Date: ${candle.date}'),
          Text('Close: ${candle.close}'),
          ...candle.indicators.entries.map(
            (entry) => Text('${entry.key}: ${entry.value?.toStringAsFixed(2)}'),
          ),
        ],
      ),
    ),
  );
}