I don't know if this thread is still active but I stumbled upon it while looking for answers for a QtWebkit problem I'm facing. Anyway...

I would go about this by using my own QNetworkAccessManager based class. Create a slot function that is connected to the finished signal from that class. I haven't tested this theory, but it should be something along the lines of -

Qt Code:
  1. void QNAMProxy::HandleFinished( QNetworkReply* reply ) {
  2. if( reply->error( )) {
  3. // Something went wrong
  4. } else {
  5. QUrl url = reply->url( );
  6. //TODO Parse the URL to create your local path
  7. QFile file( "Parsed local file name" );
  8. if (!file.open(QIODevice::WriteOnly)) {
  9. // Some problem with creating the file to write
  10. } else {
  11. file.write( reply->readAll( ));
  12. file.close( );
  13. }
  14. }
  15. }
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This should give you the basis of what you need.