from PyQt4 import QtCore, QtGui

if __name__ == "__main__":
   app = QtGui.QApplication([])

   scene = QtGui.QGraphicsScene(0.0, 0.0, 600.0, 600.0)
   view = QtGui.QGraphicsView(scene)
   view.setWindowTitle("Dialog")

   panel = QtGui.QGraphicsWidget()
   scene.addItem(panel)
   layout = QtGui.QGraphicsGridLayout()
   panel.setLayout(layout)
   
   proxy = QtGui.QGraphicsProxyWidget()
   # File dialog embeds properly
   dialog = QtGui.QFileDialog()
   # Embedding a color dialog causes an additional window to be created.
   #dialog = QtGui.QColorDialog()
   proxy.setWidget(dialog)

   layout.addItem(proxy, 0, 0, 1, 1)

   view.show()
   app.exec_()