HandlePublish

gistfile1.txt

    auto diagram_context = dynamic_cast<const DiagramContext<T>*>(&context);
    DRAKE_DEMAND(diagram_context != nullptr);

    for (const auto& action : sub_actions) {
      const int index = action.first;
      const UpdateActions<T>& action_details = action.second;
      DRAKE_DEMAND(index >= 0 && index < num_subsystems());

      const Context<T>* subcontext =
          diagram_context->GetSubsystemContext(index);
      DRAKE_DEMAND(subcontext != nullptr);
      for (const DiscreteEvent<T>& event : action_details.events) {
        if (event.action == DiscreteEvent<T>::kPublishAction) {
          sorted_systems_[index]->Publish(*subcontext, event);
        }
      }
    }