diff --git a/Modules/Core/src/Interactions/mitkDisplayActionEventHandler.cpp b/Modules/Core/src/Interactions/mitkDisplayActionEventHandler.cpp
index 6702cbae73..c5e450ee87 100644
--- a/Modules/Core/src/Interactions/mitkDisplayActionEventHandler.cpp
+++ b/Modules/Core/src/Interactions/mitkDisplayActionEventHandler.cpp
@@ -1,73 +1,76 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical Image Computing.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "mitkDisplayActionEventHandler.h"
 
 void mitk::DisplayActionEventHandler::SetObservableBroadcast(mitk::DisplayActionEventBroadcast* observableBroadcast)
 {
   if (m_ObservableBroadcast == observableBroadcast)
   {
     // no need to update the broadcast class
     return;
   }
 
-  if (m_ObservableBroadcast.IsNotNull())
+  if (!m_ObservableBroadcast.IsExpired())
   {
+    auto observableBroadcastPtr = m_ObservableBroadcast.Lock();
+
     // remove current observer
     for (const auto& tag : m_ObserverTags)
     {
-      m_ObservableBroadcast->RemoveObserver(tag);
+      observableBroadcastPtr->RemoveObserver(tag);
     }
     m_ObserverTags.clear();
   }
 
-  // set new broadcast class (possibly nullptr)
+  // set new broadcast class
   m_ObservableBroadcast = observableBroadcast;
 }
 
 mitk::DisplayActionEventHandler::OberserverTagType mitk::DisplayActionEventHandler::ConnectDisplayActionEvent(const mitk::DisplayActionEvent& displayActionEvent,
   const mitk::StdFunctionCommand::ActionFunction& actionFunction,
   const mitk::StdFunctionCommand::FilterFunction& filterFunction)
 {
-  // #TODO: change function call for new mitk::WeakPointer
-  if (m_ObservableBroadcast.IsNull())
+  if (m_ObservableBroadcast.IsExpired())
   {
     mitkThrow() << "No display action event broadcast class set to observe. Use 'SetObservableBroadcast' before connecting events.";
   }
 
+  auto observableBroadcast = m_ObservableBroadcast.Lock();
   auto command = mitk::StdFunctionCommand::New();
   command->SetCommandAction(actionFunction);
   command->SetCommandFilter(filterFunction);
-  OberserverTagType tag = m_ObservableBroadcast->AddObserver(displayActionEvent, command);
+  OberserverTagType tag = observableBroadcast->AddObserver(displayActionEvent, command);
   m_ObserverTags.push_back(tag);
   return tag;
 }
 
 void mitk::DisplayActionEventHandler::DisconnectObserver(OberserverTagType observerTag)
 {
   // #TODO: change function call for new mitk::WeakPointer
-  if (m_ObservableBroadcast.IsNull())
+  if (m_ObservableBroadcast.IsExpired())
   {
     mitkThrow() << "No display action event broadcast class set to observe. Use 'SetObservableBroadcast' before disconnecting observer.";
   }
 
+  auto observableBroadcast = m_ObservableBroadcast.Lock();
   std::vector<OberserverTagType>::iterator observerTagPosition = std::find(m_ObserverTags.begin(), m_ObserverTags.end(), observerTag);
   if (observerTagPosition != m_ObserverTags.end())
   {
-    m_ObservableBroadcast->RemoveObserver(observerTag);
+    observableBroadcast->RemoveObserver(observerTag);
     m_ObserverTags.erase(observerTagPosition);
   }
 }
diff --git a/Modules/Core/src/Interactions/mitkStdDisplayActionEventHandler.cpp b/Modules/Core/src/Interactions/mitkStdDisplayActionEventHandler.cpp
index 06eea8b3bb..95bae2ae2a 100644
--- a/Modules/Core/src/Interactions/mitkStdDisplayActionEventHandler.cpp
+++ b/Modules/Core/src/Interactions/mitkStdDisplayActionEventHandler.cpp
@@ -1,44 +1,45 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical Image Computing.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "mitkStdDisplayActionEventHandler.h"
 
 // mitk core
 #include "mitkDisplayActionEventFunctions.h"
 
 // itk
 #include <itkEventObject.h>
 
 void mitk::StdDisplayActionEventHandler::InitStdActions()
 {
-  // #TODO: change function call for new mitk::WeakPointer
-  if (m_ObservableBroadcast.IsNull())
+  if (m_ObservableBroadcast.IsExpired())
   {
     mitkThrow() << "No display action event broadcast class set to observe. Use 'SetObservableBroadcast' before initializing actions.";
   }
 
+  auto observableBroadcast = m_ObservableBroadcast.Lock();
+
   StdFunctionCommand::ActionFunction actionFunction = DisplayActionEventFunctions::MoveSenderCameraAction();
   ConnectDisplayActionEvent(DisplayMoveEvent(nullptr, Vector2D()), actionFunction);
 
   actionFunction = DisplayActionEventFunctions::SetCrosshairAction();
   ConnectDisplayActionEvent(DisplaySetCrosshairEvent(nullptr, Point3D()), actionFunction);
 
   actionFunction = DisplayActionEventFunctions::ZoomSenderCameraAction();
   ConnectDisplayActionEvent(DisplayZoomEvent(nullptr, 0.0, Point2D()), actionFunction);
 
   actionFunction = DisplayActionEventFunctions::ScrollSliceStepperAction();
   ConnectDisplayActionEvent(DisplayScrollEvent(nullptr, 0), actionFunction);
 }