docs: def setCentralWidget(self, widget):
          """
          Sets the central widget for this overlay to the inputed widget.
  
          :param      widget | <QtGui.QWidget>
          """
          self._centralWidget = widget
  
          if widget is not None:
              widget.setParent(self)
  
              widget.installEventFilter(self)
  
              # create the drop shadow effect
              effect = QtGui.QGraphicsDropShadowEffect(self)
              effect.setColor(QtGui.QColor('black'))
              effect.setBlurRadius(80)
              effect.setOffset(0, 0)
              widget.setGraphicsEffect(effect)