title: Accessing to files inside obb expansion file
body: <p>I'm following all official expansion files guides, but i can't find it. I'm unable to access the contained obb file i need.</p>
  
  <p>I need 6 audio files (80Mb) that i "stored" (uncompressed) in a zip file and renamed as 'main.2001.test.expansion.proj.obb' and stored in '/mnt/sdcard/Android/obb/test.expansion.proj/'</p>
  
  <p>I'll try to access to the files</p>
  
  <pre><code>String mainFileName = Helpers.getExpansionAPKFileName(this,true,2001);
  if(!Helpers.doesFileExist(this, mainFileName, 27959282L, false))
  {
      //download
  } else {
      Log.d("test_file","file exist");
  }
  
  ZipResourceFile expansionFile = APKExpansionSupport.getAPKExpansionZipFile(this,2001,2001);
  if(expansionFile!=null)
  {
      ZipEntryRO[] ziro = expansionFile.getAllEntries();
      for (ZipEntryRO entry : ziro) {
          Log.d("test_files_zip", "fileZip filename: "+entry.getZipFileName());
          try{
              AssetFileDescriptor ro = entry.getAssetFileDescriptor();
              Log.d("test_files_zip", "--fileZip getfiledescriptor.tostring: "+ro.getFileDescriptor().toString());
              Log.d("test_files_zip", "--fileZip createinputstring.tostring: "+ro.createInputStream().toString());
  
              AssetFileDescriptor assetFileDescriptor = expansionFile.getAssetFileDescriptor(entry.getZipFileName()+"/audio02.mp3");
              if(assetFileDescriptor!=null) {
                  Log.d("test_files_mp3", "length: "+assetFileDescriptor.getLength()); //checking it exists
              }
          }catch (IOException e){ Log.e("test_exp","IoExcp: "+e.getMessage()); }
      }
  }
  </code></pre>
  
  <p>In -> assetFileDescriptor = expansionFile.getAssetFileDescriptor(.....); i've tried all i figuret out and found in different places, but i was unable to take the file.
  Is there any way to get the file from its name if it's inside the zip?</p>
  
  <p>The app should play these files in an specificorder and we don't want to unzip the files and make them ""public"".</p>
  
  <hr>
  
  <p>Edited. Answer to myself</p>
  
  <p>Found, it was a line i didn't understand when i firstly read it or i simply miss it.</p>
  
  <pre><code>ZipResourceFile expansionFile = APKExpansionSupport.getAPKExpansionZipFile(this,2001,2001);
  if(expansionFile!=null){
          FileDescriptor fd = expansionFile.getAssetFileDescriptor("audio_01.mp3");
          //or
          InputStream is = expansionFile.getInputStream("audio_01.mp3");
      }
  </code></pre>