I sent a content image to QuickBlox server. but when i get back. i found nullPointerError

Question

I am creating a chatting app. and i what to send content(Image, Video, Audio, Location, Contact) in Private and Group. for sending image i used this code

attachInfoButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                sendImage();

            }
        });

         selectImage();





    }

    private void sendImage(){
        File filePhoto = fileUpload;
        System.out.println("Send Image..>>"+fileUpload);
        Boolean fileIsPublic = true;
        QBContent.uploadFileTask(filePhoto, fileIsPublic, null, new QBEntityCallbackImpl<QBFile>() {
            @Override
            public void onSuccess(QBFile file, Bundle params) {
                 String publicUrl = file.getPublicUrl();

                 System.out
                  .println("==========image uploaded success++++++++"
                    + publicUrl);

                 Integer id = file.getId();

                System.out
                  .println("===================image id+++++++++++"
                    + id + "");

                // create a message
                QBChatMessage chatMessage = new QBChatMessage();
                chatMessage.setProperty("save_to_history", "1"); // Save a message to history

                // attach a photo
                QBAttachment attachment = new QBAttachment("photo");
                attachment.setId(file.getId().toString());
                chatMessage.addAttachment(attachment);


                // send a message
                // ...
                Intent a =new Intent(ImageFileAttachActivity.this, ChatActivity.class);
                startActivity(a);
            }

            @Override
            public void onError(List<String> errors) {
                // error
            }
        });

//      Intent a =new Intent(ImageFileAttachActivity.this, ChatActivity.class);
//      startActivity(a);
    }



    public String getPath(Uri uri) {
        String[] projection = { MediaStore.Images.Media.DATA };
        Cursor cursor = managedQuery(uri, projection, null, null, null);
        if (cursor != null) {
            // HERE YOU WILL GET A NULLPOINTER IF CURSOR IS NULL
            // THIS CAN BE, IF YOU USED OI FILE MANAGER FOR PICKING THE MEDIA
            int column_index = cursor
                    .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            cursor.moveToFirst();
            return cursor.getString(column_index);
        } else
            return null;
    }

    public void decodeFile(String filePath) {
        // Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(filePath, o);

        // The new size we want to scale to
        final int REQUIRED_SIZE = 1024;

        // Find the correct scale value. It should be the power of 2.
        int width_tmp = o.outWidth, height_tmp = o.outHeight;
        int scale = 1;
        while (true) {
            if (width_tmp < REQUIRED_SIZE && height_tmp < REQUIRED_SIZE)
                break;
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }

        // Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        bitmap = BitmapFactory.decodeFile(filePath, o2);

        attachInfoImage.setImageBitmap(bitmap);

    }

    private void selectImage() {
        final CharSequence[] items = { "Take Photo", "Choose from Library",
                "Cancel" };

        AlertDialog.Builder builder = new AlertDialog.Builder(
                ImageFileAttachActivity.this);
        builder.setTitle("Add Photo!");
        builder.setItems(items, new DialogInterface.OnClickListener() {

            @Override
            public void onClick(DialogInterface dialog, int item) {
                if (items[item].equals("Take Photo")) {
                    Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
                    startActivityForResult(intent, REQUEST_CAMERA);
                } else if (items[item].equals("Choose from Library")) {
                    Intent intent = new Intent(
                            Intent.ACTION_PICK,
                            android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                    intent.setType("image/*");
                    startActivityForResult(
                            Intent.createChooser(intent, "Select File"),
                            SELECT_FILE);
                } else if (items[item].equals("Cancel")) {
                    dialog.dismiss();
                }
            }
        });
        builder.show();
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (resultCode == Activity.RESULT_OK) {
            if (requestCode == SELECT_FILE)
                onSelectFromGalleryResult(data);
            else if (requestCode == REQUEST_CAMERA)
                onCaptureImageResult(data);
        }
    }

    private void onCaptureImageResult(Intent data) {
        Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        thumbnail.compress(Bitmap.CompressFormat.JPEG, 90, bytes);

        File destination = new File(Environment.getExternalStorageDirectory(),
                System.currentTimeMillis() + ".jpg");

        fileUpload=destination;

    //  new ProfilePicUpload().execute();

        FileOutputStream fo;
        try {
            destination.createNewFile();
            fo = new FileOutputStream(destination);
            fo.write(bytes.toByteArray());
            fo.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        attachInfoImage.setImageBitmap(thumbnail);
    }

    @SuppressWarnings("deprecation")
    private void onSelectFromGalleryResult(Intent data) {
        Uri selectedImageUri = data.getData();
        String[] projection = { MediaColumns.DATA };
        Cursor cursor = managedQuery(selectedImageUri, projection, null, null,
                null);
        int column_index = cursor.getColumnIndexOrThrow(MediaColumns.DATA);
        cursor.moveToFirst();

        String selectedImagePath = cursor.getString(column_index);

        fileUpload = new File(selectedImagePath);

    //  new ProfilePicUpload().execute();

        Bitmap bm;
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(selectedImagePath, options);
        final int REQUIRED_SIZE = 200;
        int scale = 1;
        while (options.outWidth / scale / 2 >= REQUIRED_SIZE
                && options.outHeight / scale / 2 >= REQUIRED_SIZE)
            scale *= 2;
        options.inSampleSize = scale;
        options.inJustDecodeBounds = false;
        bm = BitmapFactory.decodeFile(selectedImagePath, options);

        attachInfoImage.setImageBitmap(bm);
    }

and I am successfully send Image to the QuickBlox server.and want to get this image for this code...

///////////////////// Download Image\\\\\\\\\\\\\\\\\\
    @SuppressWarnings("deprecation")
    public void processMessage(QBChat chat, final QBChatMessage chatMessage) {
        for(QBAttachment attachment : chatMessage.getAttachments()){
            final String fileId = attachment.getId();

            QBContent.downloadFile(fileId, new QBEntityCallbackImpl<InputStream>() {
                @SuppressWarnings("unused")
                public void onComplete(Result result) {
                    if (result.isSuccess()) {
                        QBFileResult fileResult = (QBFileResult) result;
                        QBFile file = fileResult.getFile();
                        String fileURL = file.getPublicUrl();
                    } 
                }
            });
        }
    }

But when i want to get that image then its create null pointer error.. i can't understand. where i'm wrong can you Please... and also provide example to create send content(Video, Audio, Location, Contact). Please Help me.