Modify callbacks init

micro_ros_agent/include/agent/Agent.hpp

@@ -51,7 +51,7 @@ public:
     void stop();
 
 private:
-
+    bool initialized = false;
     eprosima::uxr::AgentInstance& xrce_dds_agent_instance_;
     std::map<eprosima::fastdds::dds::DomainId_t, std::shared_ptr<graph_manager::GraphManager>> graph_manager_map_;
 

micro_ros_agent/src/agent/Agent.cpp

@@ -23,6 +23,26 @@ namespace agent {
 Agent::Agent()
     : xrce_dds_agent_instance_(xrce_dds_agent_instance_.getInstance())
 {
+}
+
+Agent& Agent::getInstance()
+{
+    static Agent instance;
+    return instance;
+}
+
+bool Agent::create(
+        int argc,
+        char** argv)
+{
+    stop();
+
+    bool result = xrce_dds_agent_instance_.create(argc, argv);
+
+    if (result && !initialized)
+    {
+        initialized = true;
+
         /**
          * Add CREATE_PARTICIPANT callback.
          */
@@ -159,18 +179,7 @@ Agent::Agent()
             std::move(on_delete_datareader));
     }
 
-Agent& Agent::getInstance()
+    return result;
-{
-    static Agent instance;
-    return instance;
-}
-
-bool Agent::create(
-        int argc,
-        char** argv)
-{
-    stop();
-    return xrce_dds_agent_instance_.create(argc, argv);
 }
 
 void Agent::run()