docs: def markCollapsed( self, direction, sizes ):
          """
          Updates the interface to reflect that the splitter is collapsed.
          
          :param      direction | <XSplitterHandle.CollapseDirection>
                      sizes     | [<int>, ..]
          """
          self._collapsed = True
          self._storedSizes = sizes[:]
          
          if ( direction == XSplitterHandle.CollapseDirection.Before ):
              if ( self.orientation() == Qt.Horizontal ):
                  self._collapseAfter.setArrowType( Qt.RightArrow )
                  self._collapseBefore.setArrowType( Qt.RightArrow )
              else:
                  self._collapseAfter.setArrowType( Qt.DownArrow )
                  self._collapseBefore.setArrowType( Qt.DownArrow )
          else:
              if ( self.orientation() == Qt.Horizontal ):
                  self._collapseAfter.setArrowType( Qt.LeftArrow )
                  self._collapseBefore.setArrowType( Qt.LeftArrow )
              else:
                  self._collapseAfter.setArrowType( Qt.UpArrow )
                  self._collapseAfter.setArrowType( Qt.UpArrow )