Looks up a reference from the widget based on its object name.
        
        :param      name | <str>
                    cls  | <subclass of QtGui.QObject>
        
        :return     <QtGui.QObject> || None

def findReference(self, name, cls=QtGui.QWidget):
        """
        Looks up a reference from the widget based on its object name.
        
        :param      name | <str>
                    cls  | <subclass of QtGui.QObject>
        
        :return     <QtGui.QObject> || None
        """
        return self.scene().findReference(name, cls)