Query query = new Query.Builder().addFilter(Filters.and(Filters.eq(SearchableField.TITLE, FOLDER_NAME), Filters.eq(SearchableField.TRASHED, false)))
                        .build();
        Drive.DriveApi.query(mGoogleApiClient, query).setResultCallback(new ResultCallback<DriveApi.MetadataBufferResult>() {
            @Override public void onResult(DriveApi.MetadataBufferResult result) {
                if (!result.getStatus().isSuccess()) {
                    Log.e(TAG, "Cannot create folder in the root.");
                } else {
                    boolean isFound = false;
                    for (Metadata m : result.getMetadataBuffer()) {
                        if (m.getTitle().equals(FOLDER_NAME)) {
                            Log.e(TAG, "Folder exists");
                            isFound = true;
                            DriveId driveId = m.getDriveId();
                            create_file_in_folder(driveId);
                            break;
                        }
                    }
                    if (!isFound) {
                        Log.i(TAG, "Folder not found; creating it.");
                        MetadataChangeSet changeSet = new MetadataChangeSet.Builder().setTitle(FOLDER_NAME).build();
                        Drive.DriveApi.getRootFolder(mGoogleApiClient)
                                .createFolder(mGoogleApiClient, changeSet)
                                .setResultCallback(new ResultCallback<DriveFolder.DriveFolderResult>() {
                                    @Override public void onResult(DriveFolder.DriveFolderResult result) {
                                        if (!result.getStatus().isSuccess()) {
                                            Log.e(TAG, "Error while trying to create the folder");
                                        } else {
                                            Log.i(TAG, "Created a folder");
                                            DriveId driveId = result.getDriveFolder().getDriveId();
                                            create_file_in_folder(driveId);
                                        }
                                    }
                                });
                    }
                }
            }
        });