unable to load asset "

[meydayapp]

Bug description

I copied the exact same code from the example

but I get this error

[ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: Unable to load asset: "packages/timezone/data/latest_all.tzf". The asset does not exist or has empty data. #0 PlatformAssetBundle.load.<anonymous closure> (package:flutter/src/services/asset_bundle.dart:333:13) <asynchronous suspension> #1 _SfCalendarState._loadDataBase (package:syncfusion_flutter_calendar/src/calendar/sfcalendar.dart:4228:31) <asynchronous suspension> #2 _SfCalendarState.initState.<anonymous closure> (package:syncfusion_flutter_calendar/src/calendar/sfcalendar.dart:2880:26) <asynchronous suspension>

so I added this to the main
https://github.com/syncfusion/flutter-widgets/blob/master/packages/syncfusion_flutter_calendar/example/lib/main.dart

Steps to reproduce

import 'package:flutter/material.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:hive_flutter/hive_flutter.dart';
import 'package:shadcn_flutter/shadcn_flutter.dart';
import 'package:timezone/data/latest_all.dart' as tz;
import 'package:timezone/timezone.dart' as tz;

import 'app.dart';
import 'core/injection_container.dart';
import 'features/weather/domain/entities/weather_model.dart';

void main() async {
WidgetsFlutterBinding.ensureInitialized();

// Load environment variables
await dotenv.load(fileName: "api_keys.env");

// Initialize Hive
await Hive.initFlutter();
Hive.registerAdapter(WeatherModelAdapter());
await Hive.openBox('weatherBox');

// Initialize dependencies
await initializeDependencies();

// Initialize timezone data
tz.initializeTimeZones();
tz.setLocalLocation(tz.getLocation('America/Detroit'));

runApp(const MyApp());
}

Code sample

Code sample

pubspec.yaml

dependencies:
  flutter:
    sdk: flutter
  flutter_localizations:
    sdk: flutter

  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.8
  country_flags: ^3.2.0
  cross_file: ^0.3.4+2
  data_widget: ^0.0.2
  gap: ^3.0.1
  skeletonizer: ^1.4.3
  phonecodes: ^0.0.4
  syntax_highlight: ^0.4.0
  email_validator: ^3.0.0
  expressions: ^0.2.5+2
  image: ^4.5.4
  amplify_flutter: ^2.6.1
  amplify_auth_cognito: ^2.6.1
  amplify_authenticator: ^2.3.3
  amplify_api: ^2.6.1
  flutter_riverpod: ^2.6.1
  flutter_iconly: ^1.0.2
  iconly: ^1.0.1
  weather_icons: ^3.0.0
  go_router: ^14.8.1
  flutter_animate: ^4.5.2
  lucide_icons: ^0.257.0
  two_dimensional_scrollables: ^0.3.3
  universal_image: ^1.0.9
  flutter_svg: ^2.0.17
  multi_split_view: ^3.6.0
  awesome_flutter_extensions: ^1.3.0
  flutter_solidart: ^1.7.1
  get: ^4.7.2
  collection: ^1.19.1
  flutter_bloc: ^9.1.0
  cached_network_image: ^3.4.1
  file_picker: ^9.2.1
  geolocator: ^14.0.0
  geocoding: ^3.0.0
  flutter_dotenv: ^5.2.1
  equatable: ^2.0.7
  amplify_storage_s3: ^2.6.1
  dart_openai: ^5.1.0
  get_it: ^8.0.3
  intl: ^0.19.0
  floor: ^1.5.0
  retrofit: ^4.4.2
  ionicons: ^0.2.2
  url_launcher: ^6.3.1
  image_picker: ^1.1.2
  dio: ^5.8.0+1
  syncfusion_flutter_charts: ^29.1.38
  http: ^1.3.0
  hive: ^2.2.3
  hive_flutter: ^1.1.0
  spritewidget: ^2.0.1
  connectivity: ^3.0.6
  shared_preferences: ^2.5.3
  line_icons: ^2.0.3
  webview_flutter: ^4.11.0
  auto_size_text: ^3.0.0
  expandable: ^5.0.1
  flutter_spinkit: ^5.2.1
  package_info: ^2.0.2
  flutter_staggered_grid_view: ^0.7.0
  syncfusion_flutter_calendar: ^29.1.39
#  timezone: ^0.10.0
#  flutter_native_timezone: ^2.0.0
  uuid: ^4.5.1
  timezone: ^0.10.0



dev_dependencies:
  flutter_test:
    sdk: flutter


  flutter_lints: ^5.0.0
  solidart_lint: ^1.1.2
  custom_lint: ^0.6.10
  build_runner: ^2.4.15
  retrofit_generator: ^9.1.9
  floor_generator: ^1.5.0
  change_app_package_name: ^1.5.0
  hive_generator: ^2.0.1

flutter:

  uses-material-design: true
  generate: true

  assets:

    #timezone
    - assets/packages/timezone/data/latest_all.tzf

import 'package:shadcn_flutter/shadcn_flutter.dart';
import 'package:syncfusion_flutter_calendar/calendar.dart' as sf;

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

  @override
  State<ExamplePage> createState() => _ExamplePageState();
}

class _ExamplePageState extends State<ExamplePage> {
  late MeetingDataSource _events;

  @override
  void initState() {
    super.initState();
    _events = MeetingDataSource(_getInitialMeetings());
  }

  List<Meeting> _getInitialMeetings() {
    final now = DateTime.now();
    return [
      Meeting(
        'Initial Meeting',
        now.add(const Duration(hours: 1)),
        now.add(const Duration(hours: 2)),
        Colors.blue,
        false,
      ),
    ];
  }

  void _addNewMeeting() {
    final now = DateTime.now();
    final newMeeting = Meeting(
      'New Event',
      now.add(const Duration(hours: 3)),
      now.add(const Duration(hours: 4)),
      Colors.green,
      false,
    );

    setState(() {
      _events.appointments!.add(newMeeting);
      _events.notifyListeners(sf.CalendarDataSourceAction.add, [newMeeting]);
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      child: Column(
        children: [
          Row(
            children: [
              const Text('Day View Calendar'),
              IconButton.ghost(
                onPressed: _addNewMeeting,
                icon: const Icon(Icons.add),
              ),
            ],
          ),
          Expanded(
            child: sf.SfCalendar(
              view: sf.CalendarView.day,
              dataSource: _events,
              todayHighlightColor: Colors.red,
              showNavigationArrow: true,
              showCurrentTimeIndicator: true,
            ),
          ),
        ],
      ),
    );
  }
}

/// Custom meeting class
class Meeting {
  Meeting(this.eventName, this.from, this.to, this.background, this.isAllDay);

  final String eventName;
  final DateTime from;
  final DateTime to;
  final Color background;
  final bool isAllDay;
}

/// DataSource using the custom `Meeting` model
class MeetingDataSource extends sf.CalendarDataSource {
  MeetingDataSource(List<Meeting> source) {
    appointments = source;
  }

  Meeting _getMeeting(int index) => appointments![index] as Meeting;

  @override
  DateTime getStartTime(int index) => _getMeeting(index).from;

  @override
  DateTime getEndTime(int index) => _getMeeting(index).to;

  @override
  String getSubject(int index) => _getMeeting(index).eventName;

  @override
  Color getColor(int index) => _getMeeting(index).background;

  @override
  bool isAllDay(int index) => _getMeeting(index).isAllDay;
}

[Add your code here]

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Screenshots or Video

Screenshots / Video demonstration

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Stack Traces

Stack Traces

Performing hot restart...
Syncing files to device iPhone SE (3rd generation)...
Restarted application in 704ms.
[ERROR:flutter/runtime/dart_vm_initializer.cc(40)] Unhandled Exception: Unable to load asset: "packages/timezone/data/latest_all.tzf".
The asset does not exist or has empty data.
#0      PlatformAssetBundle.load.<anonymous closure> (package:flutter/src/services/asset_bundle.dart:333:13)
<asynchronous suspension>
#1      _SfCalendarState._loadDataBase (package:syncfusion_flutter_calendar/src/calendar/sfcalendar.dart:4228:31)
<asynchronous suspension>
#2      _SfCalendarState.initState.<anonymous closure> (package:syncfusion_flutter_calendar/src/calendar/sfcalendar.dart:2880:26)
<asynchronous suspension>

On which target platforms have you observed this bug?

iOS

Flutter Doctor output

Doctor output

emilioboves@Emilios-Mac-Studio data % flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.29.2, on macOS 15.3 24D60 darwin-arm64, locale en-CA)
[✓] Android toolchain - develop for Android devices (Android SDK version 35.0.1)
[✓] Xcode - develop for iOS and macOS (Xcode 16.2)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2024.2)
[✓] VS Code (version 1.98.2)
[✓] Connected device (4 available)
    ! Error: Browsing on the local area network for Emilio’s iphone . Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
    ! Error: Browsing on the local area network for Emilio’s iphone . Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
[✓] Network resources

• No issues found!
emilioboves@Emilios-Mac-Studio data % 

[Mugunthan-Ramalingam]

Hi @meydayapp,

We have checked the shared code snippet with SfCalendar using version 29.1.41. However, we were unable to reproduce the issue on our end. Please check the attached sample, and if you are still experiencing the issue, we request that you replicate it in the attached sample and provide us with more details regarding the specific scenario in which you are encountering this issue. This will help us to assist you more effectively.

Screenshot:

Sample: gh_2346.zip

Regards,
Mugunthan.