Returns the total width for all the pixmaps for this widget.
        
        :return     <int>

def calculateSceneWidth(self):
        """
        Returns the total width for all the pixmaps for this widget.
        
        :return     <int>
        """
        widths = []
        
        w = self.width() / 2.0
        h = self.height() / 2.0
        
        for item in self.scene().items():
            pixmap = item.basePixmap()
            thumb = pixmap.scaled(pixmap.width(), h, Qt.KeepAspectRatio)
            widths.append(thumb.width())
            item.setPixmap(thumb)
        
        return sum(widths) + self.spacing() * (self.count() - 1) + w