using dynamic request_attribute method for the example

closes #2422

git-svn-id: http://www.openmesh.org/svnrepo/OpenMesh/trunk@1242 fdac6126-5c0c-442c-9429-916003d36597

Doc/Tutorial/07b-delete_geometry/delete_geometry.cc

@@ -51,9 +51,6 @@
 
 struct MyTraits : public OpenMesh::DefaultTraits
 {
-  VertexAttributes(OpenMesh::Attributes::Status);
-  FaceAttributes(OpenMesh::Attributes::Status);
-  EdgeAttributes(OpenMesh::Attributes::Status);
 };
 
 
@@ -67,6 +64,11 @@ int main()
 {
   MyMesh mesh;
 
+  // the request has to be called before a vertex/face/edge can be deleted. it grants access to the status attribute
+  mesh.request_face_status();
+  mesh.request_edge_status();
+  mesh.request_vertex_status();
+
   // generate vertices
 
   MyMesh::VertexHandle vhandle[8];