Change notification buses to be addressed on EntityContextId, and connect the handlers to the default id. Request interfaces should not need that id as they can retrieve it from the entityId.

Signed-off-by: Danilo Aimini <82231674+AMZN-daimini@users.noreply.github.com>

Code/Framework/AzToolsFramework/AzToolsFramework/FocusMode/FocusModeNotificationBus.h

@@ -11,19 +11,28 @@
 #include <AzCore/Component/EntityId.h>
 #include <AzCore/EBus/EBus.h>
 
+#include <AzFramework/Entity/EntityContext.h>
+
 namespace AzToolsFramework
 {
     //! Used to notify when the editor focus changes.
     class FocusModeNotifications
         : public AZ::EBusTraits
     {
-    protected:
-        ~FocusModeNotifications() = default;
-
     public:
+        //////////////////////////////////////////////////////////////////////////
+        // EBusTraits overrides
+        static const AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Multiple;
+        static const AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::ById;
+        using BusIdType = AzFramework::EntityContextId;
+        //////////////////////////////////////////////////////////////////////////
+        
         //! Triggered when the editor focus is changed to a different entity.
         //! @param entityId The entity the focus has been moved to.
         virtual void OnEditorFocusChanged(AZ::EntityId entityId) = 0;
+
+    protected:
+        ~FocusModeNotifications() = default;
     };
 
     using FocusModeNotificationBus = AZ::EBus<FocusModeNotifications>;

Code/Framework/AzToolsFramework/AzToolsFramework/Prefab/PrefabFocusHandler.cpp

@@ -96,6 +96,10 @@ namespace AzToolsFramework::Prefab
             else
             {
                 containerEntityId = AZ::EntityId();
+
+                // Clear the selection
+                AzToolsFramework::SelectEntities({});
+                
             }
             
             // Focus on the descendants of the container entity

Code/Framework/AzToolsFramework/AzToolsFramework/Prefab/PrefabFocusNotificationBus.h

@@ -17,12 +17,19 @@ namespace AzToolsFramework::Prefab
     class PrefabFocusNotifications
         : public AZ::EBusTraits
     {
-    protected:
-        ~PrefabFocusNotifications() = default;
-
     public:
+        //////////////////////////////////////////////////////////////////////////
+        // EBusTraits overrides
+        static const AZ::EBusHandlerPolicy HandlerPolicy = AZ::EBusHandlerPolicy::Multiple;
+        static const AZ::EBusAddressPolicy AddressPolicy = AZ::EBusAddressPolicy::ById;
+        using BusIdType = AzFramework::EntityContextId;
+        //////////////////////////////////////////////////////////////////////////
+        
         //! Triggered when the editor focus is changed to a different prefab.
         virtual void OnPrefabFocusChanged() = 0;
+
+    protected:
+        ~PrefabFocusNotifications() = default;
     };
 
     using PrefabFocusNotificationBus = AZ::EBus<PrefabFocusNotifications>;

Code/Framework/AzToolsFramework/AzToolsFramework/UI/Outliner/EntityOutlinerTreeView.cpp

@@ -39,7 +39,12 @@ namespace AzToolsFramework
         AZ_Assert((m_editorEntityFrameworkInterface != nullptr),
             "EntityOutlinerTreeView requires a EditorEntityFrameworkInterface instance on Construction.");
 
-        FocusModeNotificationBus::Handler::BusConnect();
+        
+        AzFramework::EntityContextId editorEntityContextId = AzFramework::EntityContextId::CreateNull();
+        AzToolsFramework::EditorEntityContextRequestBus::BroadcastResult(
+            editorEntityContextId, &AzToolsFramework::EditorEntityContextRequestBus::Events::GetEditorEntityContextId);
+
+        FocusModeNotificationBus::Handler::BusConnect(editorEntityContextId);
 
         viewport()->setMouseTracking(true);
     }

Code/Framework/AzToolsFramework/AzToolsFramework/UI/Prefab/PrefabViewportFocusPathHandler.cpp

@@ -6,15 +6,21 @@
  *
  */
 
-#include <AzToolsFramework/Prefab/PrefabFocusInterface.h>
 #include <AzToolsFramework/UI/Prefab/PrefabViewportFocusPathHandler.h>
 
+#include <AzToolsFramework/Entity/EditorEntityContextBus.h>
+#include <AzToolsFramework/Prefab/PrefabFocusInterface.h>
+
 namespace AzToolsFramework::Prefab
 {
     PrefabViewportFocusPathHandler::PrefabViewportFocusPathHandler()
     {
         // Connect to Prefab Focus Notifications
-        PrefabFocusNotificationBus::Handler::BusConnect();
+        AzFramework::EntityContextId editorEntityContextId = AzFramework::EntityContextId::CreateNull();
+        AzToolsFramework::EditorEntityContextRequestBus::BroadcastResult(
+            editorEntityContextId, &AzToolsFramework::EditorEntityContextRequestBus::Events::GetEditorEntityContextId);
+
+        PrefabFocusNotificationBus::Handler::BusConnect(editorEntityContextId);
     }
 
     PrefabViewportFocusPathHandler::~PrefabViewportFocusPathHandler()