title: How to get the identifier for a folder in Google Drive in iOS?
body: <p>I need to upload a file to a specific folder on Google Drive using my iOS app.  I know the name of the folder, but in order to upload it to a specific folder, I also need to specify the identifier for the folder.  Here is part of my code where I have hard-coded the identifier for the destination folder.  So, my questions is how do I find the identifier of the destination folder programatically.</p>
  
  <pre><code>     NSString *mimeType = @"image/png";
      NSData *imageData = UIImagePNGRepresentation(imageView.image);
  GTLUploadParameters *uploadParameters = [GTLUploadParameters uploadParametersWithData:imageData MIMEType:mimeType];
  GTLDriveFile *fileObj = [GTLDriveFile object];
  fileObj.title = @"this_is_a_test.png";
  GTLDriveParentReference *parentRef = [GTLDriveParentReference object];
  parentRef.identifier = @"0B1Em3SqS0WHrQi15SHB4OHRGd2c";
  fileObj.parents = [NSArray arrayWithObject:parentRef];
  </code></pre>