How can I listen to the state and display it on the user's screen using stream Flutter?

Question

The user transmits images that are subsequently uploaded to the server. At the same time, while some images are being uploaded, the user should be able to add other images.

I assume that this needs to be done using STREAM, but I don't understand how.

At the moment I have a UI, a Block, and a request to the server

I also need to get the loading process and display it in the UI, after 100% refresh the screen

Bloc

Future<void> _onSetScan(
  SetScanEvent event,
  Emitter<SigningDocumentsState> emit,
) async {
  final picker = ImagePicker();
  try {
    final pickerFile = await picker.pickMultiImage();

    final files = pickerFile.map<UploadFile>(
      (xFile) {
        return UploadFile(
          file: File(xFile.path),
          value: '0',
          type: event.type,
        );
      },
    ).toList();

    final receivedFiles = <UploadFile>[];

    if (files.isNotEmpty) {
      files.forEach((element) {
        final size = element.file.lengthSync() / pow(1024, 2);
        if (size > 5) {
          final msg =
              'Размер файла ${element.file.path.split('/').last} превышает 5 МБ';
          emit(
            SigningDocumentsState(
              status: SigningDocumentsStatus.largeSize,
              scans: state.scans,
              filesUploadQueue: state.filesUploadQueue,
              failureMessage: msg,
            ),
          );
        } else {
          receivedFiles.add(element);
        }
      });

    }
  } on Exception {
    emit(
      SigningDocumentsState(
        status: SigningDocumentsStatus.failure,
        scans: state.scans,
        filesUploadQueue: state.filesUploadQueue,
      ),
    );
  }
}

UI

class Contracts extends StatelessWidget {
  const Contracts({
    required this.title,
    required this.type,
    super.key,
  });

  final String title;
  final String type;

  @override
  Widget build(BuildContext context) {

    final theme = Theme.of(context);
    return BlocBuilder<SigningDocumentsBloc, SigningDocumentsState>(
      builder: (context, state) {
        final contracts =
        state.scans.where((item) => item.type == type).toList();
        print(state.filesUploadQueue);
        return Row(
          children: [
            SizedBox(
              height: theme.spacings.x20,
              width: theme.spacings.x10,
              child: OutlinedButton(
                style: OutlinedButton.styleFrom(
                  backgroundColor: theme.palette.bgQuaternary,
                  padding: EdgeInsets.symmetric(vertical: theme.spacings.x8),
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(theme.spacings.x1),
                  ),
                  side: BorderSide.none,
                ),
                onPressed: () {
                  context
                      .read<SigningDocumentsBloc>()
                      .add(SetScanEvent(type: type));
                },
                child: SvgPicture.asset(
                  AssetNames.paperClip,
                ),
              ),
            ),
            SizedBox(
              width: theme.spacings.x3,
            ),
            Expanded(
              child: SingleChildScrollView(
                scrollDirection: Axis.horizontal,
                child: Row(
                  children: [
//here
                    Row(
                      children: state.filesUploadQueue.where((item) => item.type == type).toList().map((contract) {
                        return UploadContainer(
                          value: double.parse(contract.value),
                        );
                      }).toList(),
                    ),
                    Row(
                      children: contracts.map((contract) {
                        return Contract(
                          files: contract,
                          title: title,
                          length: contracts.length,
                          index: contracts.indexOf(contract),
                        );
                      }).toList(),
                    ),
                  ],
                ),
              ),
            ),
          ],
        );
      },
    );
  }
}

UploadContainer

class UploadContainer extends StatelessWidget {
  const UploadContainer({
    required this.value,
    super.key,
  });

  final double value;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return Padding(
      padding: EdgeInsets.only(right: theme.spacings.x2),
      child: Container(
        width: theme.spacings.x20,
        height: theme.spacings.x20,
        decoration: BoxDecoration(
          border: Border.all(
            color: theme.palette.buttonDisabled,
          ),
          borderRadius: BorderRadius.circular(
            theme.spacings.x2,
          ),
        ),
        child: Center(
          child: Stack(
            children: [
              Center(
                child: CircularProgressIndicator(
                  backgroundColor: theme.palette.bgPrimary,
                  valueColor: value < 0.51
                      ? AlwaysStoppedAnimation(theme.palette.iconAccentThird)
                      : AlwaysStoppedAnimation(theme.palette.iconAccentSecond),
                  value: value,
                  strokeWidth: theme.spacings.x1,
                ),
              ),
              Center(child: Text('${(value * 100).toInt()} %', style: theme.textTheme.bodySmall,)),
            ],
          ),
        ),
      ),
    );
  }
}

Repository

@override
Future<void> setScan({
  required File file,
  required String type,
}) async {
  final name = file.path.split('/').last;
  final scan = await MultipartFile.fromFile(
    file.path,
    filename: name,
  );
  final formData = FormData.fromMap({
    'files[]': scan,
    'name': name,
    'service': 'test',
    'type': type,
  });
  await _dio.post(
    'https://test-url',
    data: formData,
    onSendProgress: (int sent, int total) {
      final percentage = ((sent/total)*100).toStringAsFixed(2); // 
    },
  );

I tried updating the state without a Stream, but when I add images in addition to those that are being loaded, they disappear from the download queue