Loads the inputed slide to the scene.
        
        :param      slide | <XWalkthroughSlide>

def load(self, slide):
        """
        Loads the inputed slide to the scene.
        
        :param      slide | <XWalkthroughSlide>
        """
        self._direction = getattr(QtGui.QBoxLayout,
                                  slide.attributes().get('direction', 'TopToBottom'),
                                  QtGui.QBoxLayout.TopToBottom)
        
        for item in slide.items():
            graphic = self.addGraphic(item.attributes().get('type', 'basic'))
            if graphic is not None:
                graphic.load(item)