Pass parameter in RxJava for OnCompleted in Android

I am uploading multiple images using RxJava. Besides uploading, I also show the progress for each uploaded file. My problem is that I need to know when the file is fully loaded (currently, the last part of the loaded progress is not emitted). Since I can upload multiple files at the same time, I need to pass the mediaId of the uploaded file. Or I should be able to get the last part of the download progress. How can i do this?

downloadThread = new Downloader(media.getMediaUrl(), media.getId(), context);
        downloadThread.start();
        downloadThread.getProgressObservable()
                .sample(30, java.util.concurrent.TimeUnit.MILLISECONDS)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(new Action1<DownloadProgressEvent>() {
                    @Override
                    public void call(DownloadProgressEvent event) {

                        ProgressBar downloadProgress = (ProgressBar) view.findViewById(R.id.download_progress);
                        if (event.getTotal() > 0) {
                            int downloadPercent = (int) ((event.getLoaded() * 100l) / event.getTotal());
                            downloadProgress.setProgress(downloadPercent);
                            Log.d(TAG, "download progress: " + String.format("%s / %s /percent: %s / mediaId: %s", event.getLoadedBytes(), event.getTotalBytes(), downloadPercent, event.getMediaId()));
                        }

                    }

                });
    }

      

        
        
        
      

    

Code from the Downloader class.

public void loadInBackground() {
        try {
            URL toDownload = new URL(url);
            HttpURLConnection urlConnection = (HttpURLConnection) toDownload.openConnection();

            urlConnection.setRequestMethod("GET");
            urlConnection.connect();

            String mimeType = MimeTypeMap.getFileExtensionFromUrl(url);
            File outFile = new File(helper.getTmpFolder() + "/" + helper.generateUniqueName() + "test." + mimeType);
            FileOutputStream fileOutput = new FileOutputStream(outFile);

            InputStream inputStream = urlConnection.getInputStream();
            totalSize = urlConnection.getContentLength();
            loadedSize = 0;

            byte[] buffer = new byte[1024];
            int bufferLength = 0; //used to store a temporary size of the buffer
            while (!killed && (bufferLength = inputStream.read(buffer)) > 0) {
                while(!running && !killed) {
                    Thread.sleep(500);
                }
                if (!killed) {
                    fileOutput.write(buffer, 0, bufferLength);
                    loadedSize += bufferLength;
                    reportProgress();
                }
            }

            fileOutput.close();
            if (killed && outFile.exists()) {
                outFile.delete();
            }

            progressSubject.onCompleted();

        } catch (MalformedURLException e) {
            e.printStackTrace();
            progressSubject.onError(e);
        } catch (IOException e) {
            e.printStackTrace();
            progressSubject.onError(e);
        } catch (InterruptedException e) {
            e.printStackTrace();
            progressSubject.onError(e);
        }
    }

    private void reportProgress() {
        progressSubject.onNext(new DownloadProgressEvent(loadedSize, totalSize, mediaId));
    }

    @Override
    public void run() {
        loadInBackground();
    }


    public Subject<DownloadProgressEvent, DownloadProgressEvent> getProgressObservable() {
        return progressSubject;
    }