m3_lightmeter/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_localizations/flutter_localizations.dart';
import 'package:lightmeter/data/permissions_service.dart';
import 'package:lightmeter/screens/settings/settings_page_route_builder.dart';
import 'package:lightmeter/screens/settings/settings_screen.dart';
import 'package:provider/provider.dart';

import 'generated/l10n.dart';
import 'models/photography_value.dart';
import 'res/dimens.dart';
import 'res/theme.dart';
import 'screens/metering/metering_bloc.dart';
import 'screens/metering/metering_screen.dart';
import 'utils/stop_type_provider.dart';

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

final RouteObserver<PageRoute> routeObserver = RouteObserver<PageRoute>();

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

  @override
  State<Application> createState() => _ApplicationState();
}

class _ApplicationState extends State<Application> with TickerProviderStateMixin {
  late final AnimationController _animationController;
  late final _settingsRouteObserver = _SettingsRouteObserver(onPush: _onSettingsPush, onPop: _onSettingsPop);

  @override
  void initState() {
    super.initState();
    final mySystemTheme = SystemUiOverlayStyle.light.copyWith(
      statusBarColor: Colors.transparent,
      statusBarBrightness: Brightness.light,
      statusBarIconBrightness: Brightness.dark,
      systemNavigationBarColor: Colors.transparent,
      systemNavigationBarIconBrightness: Brightness.dark,
    );
    SystemChrome.setSystemUIOverlayStyle(mySystemTheme);
    // 0 - collapsed
    // 1 - expanded
    _animationController = AnimationController(
      value: 0,
      duration: Dimens.durationM,
      reverseDuration: Dimens.durationSM,
      vsync: this,
    );
  }

  @override
  void dispose() {
    _animationController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Provider(
      create: (context) => PermissionsService(),
      child: StopTypeProvider(
        child: BlocProvider(
          create: (context) => MeteringBloc(context.read<StopType>()),
          child: MaterialApp(
            theme: ThemeData(
              useMaterial3: true,
              colorScheme: lightColorScheme,
            ),
            navigatorObservers: [_settingsRouteObserver],
            localizationsDelegates: const [
              S.delegate,
              GlobalMaterialLocalizations.delegate,
              GlobalWidgetsLocalizations.delegate,
              GlobalCupertinoLocalizations.delegate,
            ],
            supportedLocales: S.delegate.supportedLocales,
            home: MeteringScreen(animationController: _animationController),
            routes: {
              "metering": (context) => MeteringScreen(animationController: _animationController),
              "settings": (context) => const SettingsScreen(),
            },
          ),
        ),
      ),
    );
  }

  void _onSettingsPush() {
    if (!_animationController.isAnimating && _animationController.status != AnimationStatus.completed) {
      _animationController.forward();
    }
  }

  void _onSettingsPop() {
    Future.delayed(Dimens.durationM).then((_) {
      if (!_animationController.isAnimating && _animationController.status != AnimationStatus.dismissed) {
        _animationController.reverse();
      }
    });
  }
}

class _SettingsRouteObserver extends RouteObserver<SettingsPageRouteBuilder> {
  final VoidCallback onPush;
  final VoidCallback onPop;

  _SettingsRouteObserver({
    required this.onPush,
    required this.onPop,
  });

  @override
  void didPush(Route<dynamic> route, Route<dynamic>? previousRoute) {
    super.didPush(route, previousRoute);
    if (route is SettingsPageRouteBuilder) {
      onPush();
    }
  }

  @override
  void didPop(Route<dynamic> route, Route<dynamic>? previousRoute) {
    super.didPop(route, previousRoute);
    if (previousRoute is PageRoute && route is SettingsPageRouteBuilder) {
      onPop();
    }
  }
}