convertUriToFile

                    Uri selectedImage = data.getData(); // or your uri
                    String selectedMediaPath;

                    Cursor cursor = getActivity().getContentResolver().query(selectedImage, null,null, null, null);

                     if (cursor == null) 
                        selectedMediaPath = selectedImage.getPath;
                    else {
                        cursor.moveToFirst();
                        int idx = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
                        selectedMediaPath = cursor.getString(idx);
                    }
                    cursor.close();

                   File userPhotoFile = new File(selectedMediaPath);
                   RequestBody userFileRequest = RequestBody.create(MediaType.parse(guessContentTypeFromName(userPhotoFile.name)), userPhotoFile);
                   
                   MultipartBody.Part mediaPart; // send it with retrofit as parameter with @Part
                   try {
                      mediaPart = MultipartBody.Part.createFormData("image", userPhotoFile.getName(), userFileRequest);
                   } catch (e: IllegalArgumentException) {
                      mediaPart = MultipartBody.Part.createFormData("image", "not_supported_file_name", userFileRequest);
                   }