From cfbe76fdf639814abb92ad8d1ea30c5b21042165 Mon Sep 17 00:00:00 2001
From: John <jonawals@amazon.com>
Date: Thu, 30 Sep 2021 17:29:32 +0100
Subject: [PATCH] Add call site for activating/deactivating Focus.

Signed-off-by: John <jonawals@amazon.com>
---
 .../FocusMode/FocusModeSystemComponent.cpp         | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/Code/Framework/AzToolsFramework/AzToolsFramework/FocusMode/FocusModeSystemComponent.cpp b/Code/Framework/AzToolsFramework/AzToolsFramework/FocusMode/FocusModeSystemComponent.cpp
index e1c04fcb93..3fafb4db81 100644
--- a/Code/Framework/AzToolsFramework/AzToolsFramework/FocusMode/FocusModeSystemComponent.cpp
+++ b/Code/Framework/AzToolsFramework/AzToolsFramework/FocusMode/FocusModeSystemComponent.cpp
@@ -10,6 +10,7 @@
 
 #include <AzToolsFramework/API/ViewportEditorModeTrackerInterface.h>
 #include <AzToolsFramework/FocusMode/FocusModeSystemComponent.h>
+#include <AzToolsFramework/API/ViewportEditorModeTrackerInterface.h>
 
 namespace AzToolsFramework
 {
@@ -66,7 +67,18 @@ namespace AzToolsFramework
     {
         m_focusRoot = entityId;
 
-        // TODO - If m_focusRoot != AZ::EntityId(), activate focus mode via ViewportEditorModeTrackerInterface; else, deactivate focus mode
+        if (auto tracker = AZ::Interface<ViewportEditorModeTrackerInterface>::Get();
+            tracker != nullptr)
+        {
+            if (!m_focusRoot.IsValid() && entityId.IsValid())
+            {
+                tracker->ActivateMode({ /* DefaultViewportId */ }, ViewportEditorMode::Focus);
+            }
+            else if (m_focusRoot.IsValid() && !entityId.IsValid())
+            {
+                tracker->DeactivateMode({ /* DefaultViewportId */ }, ViewportEditorMode::Focus);
+            }
+        }
     }
 
     void FocusModeSystemComponent::ClearFocusRoot()