[Boost-users] Adding content to a vertex in a graph

From: Stephen Torri (storri_at_[hidden])
Date: 2007-08-28 17:42:45

I made this property graph according to the documentation:

        class Component {
        public:
                typedef boost::shared_ptr<Component> ptr_t;
        };

        class My_Graph {

            typedef boost::property< boost::vertex_name_t,
                                     Component::ptr_t >
VertexProperty_t;

            typedef boost::adjacency_list<boost::vecS, // OutEdgeList
                                          boost::vecS, // VertexList
                                          boost::directedS, // Directed
                                          VertexProperty_t> //
VertexProperties
            Graph_t;

          Graph_t m_graph;
        };

I cannot see from the MutablePropertyGraph page how I am suppose to add
the VertexProperty_t to the vertex when its created. The documentation
for the MutablePropertyGraph shows a use of "add_vertex" giving a
vertex_propety_type with the graph. 

  template <class G>
  struct MutablePropertyGraphConcept
  {
    typedef typename boost::graph_traits<G>::edge_descriptor edge_descriptor;
    void constraints() {
      function_requires< MutableGraphConcept<G> >();
      v = add_vertex(vp, g);
      p = add_edge(u, v, ep, g);
    }
    G g;
    std::pair<edge_descriptor, bool> p;
    typename boost::graph_traits<G>::vertex_descriptor u, v;
    typename boost::graph_traits<G>::vertex_property_type vp;
    typename boost::graph_traits<G>::edge_property_type ep;
  };

My confusion lies in the fact that the add_vertex function requires a
vertex_property_type the first parameter. So I am unsure how to create a
vertex_property_type from a Component::ptr. Is a vertex_property_type
equivalent to a Component::ptr?

        boost::graph_traits<Graph_t>::vertex_property_type vertex_propert_obj = Component::ptr ( new Component() );
        boost::graph_traits<Graph_t>::vertex_descriptor new_vertex = add_vertex ( vertex_property_obj, m_graph );

Stephen