Implemented by subclasses to show the results of the layout generated by
realizeLayout(), by transfering the layout state to the part view graphics,
and making any changes visible in the whole view graphic.
Informs this graphic entity that external (sibling, ancestor) and
internal (self, descendant) state changes that can affect its
presentation are complete and assumed valid, and that it should
update its presentation as needed to be consistent with its
graphic state.
Default implementation: For each part model, in iterator order: If
an edge model, removes its head end vertex and forward subtree; if a
vertex model, removes it and its forward subtree.
Default implementation: For each part model, in iterator order: If
an edge model, removes its head end vertex and forward sublist; if a
vertex model, removes it and its forward sublist.
Default implementation: For each part model, in iterator order:
Calls the super method to remove and dispose the part views, then
calls prepare and realize on the whole graphic view to update the
view presentation.