downloadOfflineRegion function

Future<OfflineRegion> downloadOfflineRegion(OfflineRegionDefinition definition, { Map<String, dynamic> metadata = const {}, dynamic onEvent(DownloadRegionStatus event)?, })

Implementation

Future<OfflineRegion> downloadOfflineRegion(
  OfflineRegionDefinition definition, {
  Map<String, dynamic> metadata = const {},
  Function(DownloadRegionStatus event)? onEvent,
}) async {
  String channelName =
      'downloadOfflineRegion_${DateTime.now().microsecondsSinceEpoch}';

  await _globalChannel
      .invokeMethod('downloadOfflineRegion#setup', <String, dynamic>{
    'channelName': channelName,
  });

  if (onEvent != null) {
    EventChannel(channelName).receiveBroadcastStream().handleError((error) {
      if (error is PlatformException) {
        onEvent(Error(error));
        return Error(error);
      }
      var unknownError = Error(
        PlatformException(
          code: 'UnknowException',
          message:
              'This error is unhandled by plugin. Please contact us if needed.',
          details: error,
        ),
      );
      onEvent(unknownError);
      return unknownError;
    }).listen((data) {
      final Map<String, dynamic> jsonData = json.decode(data);
      DownloadRegionStatus? status;
      switch (jsonData['status']) {
        case 'start':
          status = InProgress(0.0);
          break;
        case 'progress':
          final dynamic value = jsonData['progress'];
          double progress = 0.0;

          if (value is int) {
            progress = value.toDouble();
          }

          if (value is double) {
            progress = value;
          }

          status = InProgress(progress);
          break;
        case 'success':
          status = Success();
          break;
      }
      onEvent(status ?? (throw 'Invalid event status ${jsonData['status']}'));
    });
  }

  final result = await _globalChannel
      .invokeMethod('downloadOfflineRegion', <String, dynamic>{
    'definition': definition.toMap(),
    'metadata': metadata,
  });

  return OfflineRegion.fromMap(json.decode(result));
}