.. _program_listing_file__tmp_ws_src_system_modes_system_modes_include_system_modes_mode_observer.hpp:

Program Listing for File mode_observer.hpp
==========================================

|exhale_lsh| :ref:`Return to documentation for file <file__tmp_ws_src_system_modes_system_modes_include_system_modes_mode_observer.hpp>` (``/tmp/ws/src/system_modes/system_modes/include/system_modes/mode_observer.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   // Copyright (c) 2018 - for information on the respective copyright owner
   // see the NOTICE file and/or the repository https://github.com/microros/system_modes
   //
   // Licensed under the Apache License, Version 2.0 (the "License");
   // you may not use this file except in compliance with the License.
   // You may obtain a copy of the License at
   //
   //     http://www.apache.org/licenses/LICENSE-2.0
   //
   // Unless required by applicable law or agreed to in writing, software
   // distributed under the License is distributed on an "AS IS" BASIS,
   // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   // See the License for the specific language governing permissions and
   // limitations under the License.
   #pragma once
   
   #include <rclcpp/rclcpp.hpp>
   
   #include <lifecycle_msgs/msg/transition_event.hpp>
   #include <lifecycle_msgs/srv/get_state.hpp>
   
   #include <map>
   #include <memory>
   #include <mutex>
   #include <string>
   #include <utility>
   
   #include "system_modes/mode.hpp"
   #include "system_modes_msgs/msg/mode_event.hpp"
   #include "system_modes_msgs/srv/get_mode.hpp"
   
   namespace system_modes
   {
   
   using std::map;
   using std::mutex;
   using std::string;
   
   using lifecycle_msgs::msg::TransitionEvent;
   using lifecycle_msgs::srv::GetState;
   using rclcpp::node_interfaces::NodeBaseInterface;
   using system_modes_msgs::msg::ModeEvent;
   using system_modes_msgs::srv::GetMode;
   
   class ModeObserver
   {
   public:
     explicit ModeObserver(std::weak_ptr<rclcpp::Node>);
     virtual ~ModeObserver() = default;
   
     virtual StateAndMode
     get(const string & part_name);
   
     virtual void
     observe(const string & part_name);
   
     virtual void
     stop_observing(const string & part_name);
   
   protected:
     virtual void
     transition_callback(
       const TransitionEvent::SharedPtr msg,
       const string & part_name);
   
     virtual void
     mode_event_callback(
       const ModeEvent::SharedPtr msg,
       const string & part_name);
   
   private:
     std::weak_ptr<rclcpp::Node> node_handle_;
     map<string, StateAndMode> cache_;
     mutable std::shared_timed_mutex mutex_;
   
     map<string, std::shared_ptr<rclcpp::Subscription<TransitionEvent>>> state_subs_;
     map<string, std::shared_ptr<rclcpp::Subscription<ModeEvent>>> mode_subs_;
   };
   
   }  // namespace system_modes