title: QT for cross platform plugin development?
body: <p>I have a pre-existing application, that calls out into a plugin library. I want the plugin library to be developed in Qt, and to be able to display a Qt UI.</p>
  
  <p>However, when I attempt to create a <code>QWidget</code> it complains that the <code>QApplication</code> needs to be created first.</p>
  
  <p>Is it not possible to use Qt to develop cross platform plugins?<br>
  E.g. a netscape plugin for Chrome or Firefox. I do not, and cannot, control the app's main loop.</p>