Uploading a file with a progress displayed using OkHttp

CountingFileRequestBody.java

public class CountingFileRequestBody extends RequestBody {

    private static final int SEGMENT_SIZE = 2048; // okio.Segment.SIZE

    private final File file;
    private final ProgressListener listener;
    private final String contentType;

    public CountingFileRequestBody(File file, String contentType, ProgressListener listener) {
        this.file = file;
        this.contentType = contentType;
        this.listener = listener;
    }

    @Override
    public long contentLength() {
        return file.length();
    }

    @Override
    public MediaType contentType() {
        return MediaType.parse(contentType);
    }

    @Override
    public void writeTo(BufferedSink sink) throws IOException {
        Source source = null;
        try {
            source = Okio.source(file);
            long total = 0;
            long read;

            while ((read = source.read(sink.buffer(), SEGMENT_SIZE)) != -1) {
                total += read;
                sink.flush();
                this.listener.transferred(total);

            }
        } finally {
            Util.closeQuietly(source);
        }
    }

    public interface ProgressListener {
        void transferred(long num);
    }

}

MyPicturesAdapter.java

public class MyPicturesAdapter extends BaseAdapter {

    private static final int ITEM_TYPE_ONLINE = 0;
    private static final int ITEM_TYPE_DISK = 1;

    private List<UserImage> userImages;
    private Context context;
    private OnActionListener onActionListener;

    private LayoutInflater inflater;

    public MyPicturesAdapter(Context context) {
        super();
        this.context = context;
        this.userImages = new ArrayList<UserImage>();
        this.inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }

    @Override
    public int getCount() {
        return userImages.size();
    }

    @Override
    public int getViewTypeCount() {
        return 2;
    }

    @Override
    public int getItemViewType(int position) {
        return getItem(position).status >= 0 ? ITEM_TYPE_ONLINE : ITEM_TYPE_DISK;
    }

    @Override
    public UserImage getItem(int position) {
        return userImages.get(position);
    }

    @Override
    public long getItemId(int position) {
        return userImages.get(position).image.hashCode();
    }

    public void clear() {
        this.userImages.clear();
    }

    public void addAll(Collection<UserImage> images) {
        if (images != null) {
            this.userImages.addAll(images);
        }
    }

    public void remove(UserImage userImage) {
        this.userImages.remove(userImage);
    }


    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        ViewHolder holder;
        if (convertView != null) {
            holder = (ViewHolder) convertView.getTag();
        } else {
            int itemType = getItemViewType(position);
            if (itemType == ITEM_TYPE_ONLINE)
                convertView = inflater.inflate(R.layout.item_my_pictures_image, parent, false);
            else
                convertView = inflater.inflate(R.layout.item_my_pictures_upload, parent, false);
            holder = new ViewHolder(convertView);
            if (itemType == ITEM_TYPE_DISK) {
                holder.cancelButtonListener = new CancelButtonListener();
                holder.statusIcon.setOnClickListener(holder.cancelButtonListener);
            }
            convertView.setTag(holder);
        }

        final UserImage userImage = getItem(position);

        if (getItemViewType(position) == ITEM_TYPE_DISK) {

            Picasso.with(holder.avatar.getContext())
                    .load(Uri.fromFile(new File(UploadsHandler.getInstance().getImagePath(userImage.image))))
                    .noFade()
                    .fit()
                    .into(holder.avatar);

            userImage.status = UploadsHandler.getInstance().getUploadStatus(userImage.image);

            holder.cancelButtonListener.updatePosition(position);

            switch (userImage.status) {
                case UploadsHandler.UPLOAD_LOADING:
                    holder.uploadProgress.setVisibility(View.VISIBLE);
                    UploadsHandler.getInstance().setProgressBar(userImage.image, holder.uploadProgress);
                    holder.statusText.setVisibility(View.GONE);
                    holder.statusIcon.setImageResource(R.drawable.icon_mb_cancelupload);
                    break;
                case UploadsHandler.UPLOAD_ERROR:
                    holder.uploadProgress.setVisibility(View.GONE);
                    holder.statusText.setVisibility(View.VISIBLE);
                    holder.statusText.setText(R.string.picture_upload_error);
                    holder.statusIcon.setImageResource(R.drawable.icon_mb_errorupload);
                    break;
                case UploadsHandler.UPLOAD_ABORTED:
                    holder.uploadProgress.setVisibility(View.GONE);
                    holder.statusText.setVisibility(View.VISIBLE);
                    holder.statusText.setText(R.string.picture_upload_aborted);
                    holder.statusIcon.setImageResource(R.drawable.icon_mb_refreshupload);
                    break;
            }

            holder.statusIndicator.setBackgroundColor(Color.TRANSPARENT);
            holder.uploadProgress.setProgress(UploadsHandler.getInstance().getProgress(userImage.image));
        } else {

            switch (userImage.status) {
                case 0:
                    holder.statusIndicator.setBackgroundColor(context.getResources().getColor(R.color.my_pictures_check_divider));
                    holder.statusIcon.setImageResource(R.drawable.icon_mb_check);
                    holder.actionIcon.setImageResource(R.drawable.icon_mb_settings);
                    break;
                // etc
            }

            holder.statusText.setText(userImage.description);

            UIUtils.loadImage(context, holder.avatar, userImage.image);

        }

        return convertView;
    }

    public void add(UserImage image) {
        this.userImages.add(image);
    }

    public void setOnActionListener(OnActionListener onActionListener) {
        this.onActionListener = onActionListener;
    }

    static class ViewHolder {
        @InjectView(R.id.user_image_avatar)
        ImageView avatar;

        @InjectView(R.id.user_image_status_indicator)
        View statusIndicator;

        @InjectView(R.id.user_image_status_icon)
        ImageView statusIcon;

        @InjectView(R.id.user_image_status_text)
        TextView statusText;

        @Optional @InjectView(R.id.user_image_upload_progress)
        ProgressBar uploadProgress;

        @Optional @InjectView(R.id.user_image_action)
        ImageView actionIcon;

        CancelButtonListener cancelButtonListener;

        public ViewHolder(View view) {
            ButterKnife.inject(this, view);
        }
    }

    public interface OnActionListener {
        public void onAction(int position);
    }

    private class CancelButtonListener implements View.OnClickListener {

        private int position;

        private void updatePosition(int pos){
            position = pos;
        }

        @Override
        public void onClick(View v) {
            if (onActionListener != null)
                onActionListener.onAction(position);

        }
    }
}

UploadsHandler.java

public class UploadsHandler {

    public static final int UPLOAD_LOADING = -1;
    public static final int UPLOAD_ABORTED = -2;
    public static final int UPLOAD_ERROR = -3;

    private static UploadsHandler ourInstance;

    private Context context;
    private volatile HashMap<String, UploadData> uploads;
    private List<Pair<String, String>> uploadTempQueue;
    private final OkHttpClient client;
    private final Gson gson;
    private final Handler handler;

    public static UploadsHandler getInstance() {
        if (ourInstance == null)
            ourInstance = new UploadsHandler(Utils.getAppContext());
        return ourInstance;
    }

    private UploadsHandler(Context context) {
        this.context = context;
        uploads = new HashMap<>();
        uploadTempQueue = new ArrayList<>();
        client = new OkHttpClient();
        gson = new Gson();
        handler = new Handler(context.getMainLooper());
    }

    /**
     * Starts uploading an image to the server
     *
     * @param apiPath   api URL; e.g. /api/userImage/upload/
     * @param imagePath Path to the image on disk
     * @param tempId    The temoporary name that the image gets until it's uploaded
     * @param callback  Callback to be executed after the upload is finished
     */
    public void uploadImage(String apiPath, String imagePath, final String tempId, final ApiCallback<StateModel> callback) {

        final UploadData uploadData = new UploadData();
        uploadData.imagePath = imagePath;
        uploadData.progressValue = 0;
        uploadData.status = UPLOAD_LOADING;
        uploadData.apiMethod = apiPath;

        final File file = new File(imagePath);
        final long totalSize = file.length();

        RequestBody requestBody = new MultipartBuilder()
                .type(MultipartBuilder.FORM)
                .addPart(
                        Headers.of("Content-Disposition", "form-data; name=\"image\"; filename=\"" + file.getName() + "\""),
                        new CountingFileRequestBody(file, "image/*", new CountingFileRequestBody.ProgressListener() {
                            @Override
                            public void transferred(long num) {
                                float progress = (num / (float) totalSize) * 100;
                                uploadData.progressValue = (int) progress;
                                handler.post(new Runnable() {
                                    @Override
                                    public void run() {
                                        updateProgressBar(tempId);
                                    }
                                });
                            }
                        })
                )
                .build();

        Request request = new Request.Builder()
                .tag(tempId)
                .url(Constants.BASE_URL + apiPath)
                .post(requestBody)
                .build();

        uploads.put(tempId, uploadData);

        Call call = client.newCall(request);

        call.enqueue(new Callback() {
            @Override
            public void onFailure(final Request request, IOException e) {
                if (Constants.DEV) {
                    e.printStackTrace();
                }

                uploads.get(tempId).progressValue = -1;
                if (uploadCanceled(tempId)) {
                    uploads.get(tempId).status = UPLOAD_ABORTED;
                } else {
                    uploads.get(tempId).status = UPLOAD_ERROR;
                }

                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        try {
                            ErrorModel body = gson.fromJson(request.body().toString(), ErrorModel.class);
                            //parse error and take action
                            callback.onError(ErrorType.UNKNOWN, null, null);
                        } catch (Throwable ex) {
                            callback.onError(ErrorType.UNKNOWN, null, null);
                        }
                    }
                });
            }

            @Override
            public void onResponse(Response response) throws IOException {
                final BaseModel<StateModel> data = gson.fromJson(response.body().charStream(), new TypeToken<BaseModel<StateModel>>() {
                }.getType());
                handler.post(new Runnable() {
                    @Override
                    public void run() {
                        if (!data.error) {
                            uploads.remove(tempId);
                            callback.onSuccess(data.data, false);
                        } else {
                            uploads.get(tempId).status = UPLOAD_ERROR;
                            uploads.get(tempId).progressValue = -1;
                            callback.onDataError(ErrorType.DATA_INPUT, data);
                        }
                    }
                });
            }
        });
    }


    public List<UserImage> getCurrentUploadsList() {
        List<UserImage> currentUploads = new ArrayList<UserImage>();

        for (Map.Entry<String, UploadData> entry : uploads.entrySet()) {
            UserImage image = new UserImage();
            image.image = entry.getKey();
            image.status = entry.getValue().status;
            currentUploads.add(image);
        }

        return currentUploads;
    }

    public boolean isUploading(String image) {
        return uploads.containsKey(image);
    }

    public String getImagePath(String image) {
        if (uploads.containsKey(image)) {
            return uploads.get(image).imagePath;
        }
        return null;
    }

    public String getApiPath(String image) {
        if (uploads.containsKey(image)) {
            return uploads.get(image).apiMethod;
        }
        return null;
    }

    public int getProgress(String image) {
        if (uploads.containsKey(image)) {
            return uploads.get(image).progressValue;
        }

        return -1;
    }

    public void setProgressBar(String image, ProgressBar progressBar) {
        if (uploads.containsKey(image)) {
            uploads.get(image).uploadProgressBar = progressBar;
        }
    }

    private void updateProgressBar(String image) {
        if (uploads.containsKey(image) && uploads.get(image).uploadProgressBar != null) {
            uploads.get(image).uploadProgressBar.setProgress(getProgress(image));
        }
    }

    public int getUploadStatus(String image) {
        if (uploads.containsKey(image))
            return uploads.get(image).status;
        return 0;
    }

    public boolean uploadCanceled(String image) {
        return uploads.containsKey(image) && uploads.get(image).canceled;
    }

    public void cancelUpload(String image) {
        if (uploads.containsKey(image)) {
            uploads.get(image).canceled = true;
            client.cancel(image);
        }
    }

    public void retryUpload(String image, ApiCallback<StateModel> callback) {
        if (uploads.containsKey(image)) {
            uploadImage(getApiPath(image), getImagePath(image), image, callback);
        }
    }

    private static class UploadData {
        ProgressBar uploadProgressBar;
        int progressValue;
        String imagePath;
        int status;
        boolean canceled;
        String apiMethod;

        UploadData() {
            progressValue = -1;
        }
    }
}