How to extract .obb file in android to resource directory?

I am using the libraries provided by the android sdk for the apk extension file to download the obb file, however I am not sure how to extract these files to the correct directory or if it is possible?

The .obb file is loading correctly and I can read the entire directory, however, as soon as I try to use any of the resources in the zipped assets folder, it doesn't find it. I followed this guide (which is basically the same everywhere: http://ankitthakkar90.blogspot.co.za/2013/01/apk-expansion-files-in-android-with.html ) But I can't find where ( or if needed) manually extract the .obb file? When the obb file is downloaded, it copies the entire .obb file to the / data directory instead of extracting the entire content.

If someone can just point me in the right direction or explain to me what I am doing wrong it will help.

.Obb file structure If I understand correctly, is APKExpansionSupport used to work with files inside the directory of the .obb file? But how do I extract the contents of the asset folders into my projects folder?

Thanx!