[Qt-interest] Drag&Drop on OS X behaves weird

[Nikos Chantziaras]

In my application, I allow drag&dropping files.  If a file is dropped 
into the application's QMainWindow, that file is opened.  To do this, I 
override dragEnterEvent(QDragEnterEvent*) and dropEvent(QDropEvent*) in 
my QMainWindow subclass.  The code is very straightforward and short:

  void dragEnterEvent( QDragEnterEvent* e )
  {
     // Only accept the event if there is exactly one URL which
     // points to a local file.
     if (e->mimeData()->hasUrls() and e->mimeData()->urls().size() == 1
         and not e->mimeData()->urls().at(0).toLocalFile().isEmpty())
     {
         e->acceptProposedAction();
     }
  }

  void dropEvent( QDropEvent* e )
  {
     if (ok_to_open_a_file) {
         schedule_file_open(e->mimeData()->urls().at(0).toLocalFile());
         e->acceptProposedAction();
     } else {
         e->ignore();
     }
  }

Is this is how the drag&drop functionality of Qt is intended to be used? 
  Because on OS X I get weird results, mainly the application not 
accepting any keyboard inputs anymore after the file is opened.  At 
least for a while (10 seconds or so.)  Furthermore, the application from 
which the drag&drop operation originated also freezes for about the same 
amount of time (in this case, the Mac Finder).  No such problems on Linux.

I'm on Qt 4.7.1.