Potentially fix gui grash

source/RobotAPI/libraries/RobotUnitDataStreamingReceiver/RobotUnitDataStreamingReceiver.cpp

@@ -47,12 +47,17 @@ namespace armarx::detail::RobotUnitDataStreamingReceiver
 
         void update(const RobotUnitDataStreaming::TimeStepSeq& data, const Ice::Current&) override
         {
+            if (_discard_data)
+            {
+                return;
+            }
             std::lock_guard g{_data_mutex};
             ARMARX_INFO << deactivateSpam()
                         << "received " << data.size() << " timesteps";
             _data.emplace_back(data);
         }
 
+        std::atomic_bool                                 _discard_data = false;
         std::mutex                                       _data_mutex;
         std::deque<RobotUnitDataStreaming::TimeStepSeq>  _data;
         Ice::Identity                                    _identity;
@@ -86,12 +91,19 @@ namespace armarx
     {
         if (_proxy)
         {
+            _receiver->_discard_data = true;
             if (!_description.entries.empty())
             {
                 _ru->stopDataStreaming(_proxy);
             }
+            auto icemanager = _obj->getArmarXManager()->getIceManager();
             auto adapter = _obj->getArmarXManager()->getAdapter();
             adapter->remove(_receiver->_identity);
+
+            while (icemanager->isObjectReachable(_receiver->_identity.name))
+            {
+                ARMARX_INFO << deactivateSpam() << "waiting until receiver is removed from ice";
+            }
         }
         _proxy    = nullptr;
         _receiver = nullptr;