Draws the overlay pixmap for this item.
        
        :param      painter | <QtGui.QPainter>
                    option  | <QtGui.QSylteOptionIndex>
                    rect    | <QtCore.QRect>
                    pixmap  | <QtGui.QIcon>

def drawOverlay(self, painter, option, rect, icon):
        """
        Draws the overlay pixmap for this item.
        
        :param      painter | <QtGui.QPainter>
                    option  | <QtGui.QSylteOptionIndex>
                    rect    | <QtCore.QRect>
                    pixmap  | <QtGui.QIcon>
        """
        if icon and not icon.isNull():
            painter.drawPixmap(rect, icon.pixmap(rect.width(), rect.height()))