5 files changed, 23 insertions, 0 deletions
diff --git a/indra/llwindow/llopenglview-objc.mm b/indra/llwindow/llopenglview-objc.mm
index de123d80d5..ee05fd5cc9 100644
--- a/indra/llwindow/llopenglview-objc.mm
+++ b/indra/llwindow/llopenglview-objc.mm
@@ -167,6 +167,9 @@ attributedStringInfo getSegments(NSAttributedString *str)
     [[NSNotificationCenter defaultCenter] addObserver:self
 											 selector:@selector(windowDidBecomeKey:) name:NSWindowDidBecomeKeyNotification
 											   object:[self window]];
+	[[NSNotificationCenter defaultCenter] addObserver:self
+											 selector:@selector(windowDidChangeScreen:) name:NSWindowDidChangeScreenNotification
+											   object:[self window]];
 
 
     NSRect wnd_rect = [[self window] frame];
@@ -206,6 +209,11 @@ attributedStringInfo getSegments(NSAttributedString *str)
     mModifiers = [NSEvent modifierFlags];
 }
 
+-(void)windowDidChangeScreen:(NSNotification *)notification;
+{
+	callWindowDidChangeScreen();
+}
+
 - (void)dealloc
 {
 	[[NSNotificationCenter defaultCenter] removeObserver:self];
diff --git a/indra/llwindow/llwindowcallbacks.cpp b/indra/llwindow/llwindowcallbacks.cpp
index 7e90ade423..94c725fc7e 100644
--- a/indra/llwindow/llwindowcallbacks.cpp
+++ b/indra/llwindow/llwindowcallbacks.cpp
@@ -180,6 +180,11 @@ BOOL LLWindowCallbacks::handleDPIChanged(LLWindow *window, F32 ui_scale_factor,
 	return FALSE;
 }
 
+BOOL LLWindowCallbacks::handleWindowDidChangeScreen(LLWindow *window)
+{
+	return FALSE;
+}
+
 void LLWindowCallbacks::handlePingWatchdog(LLWindow *window, const char * msg)
 {
 
diff --git a/indra/llwindow/llwindowcallbacks.h b/indra/llwindow/llwindowcallbacks.h
index 47d5a18858..4d753024fe 100644
--- a/indra/llwindow/llwindowcallbacks.h
+++ b/indra/llwindow/llwindowcallbacks.h
@@ -66,6 +66,7 @@ public:
 	virtual BOOL handleTimerEvent(LLWindow *window);
 	virtual BOOL handleDeviceChange(LLWindow *window);
 	virtual BOOL handleDPIChanged(LLWindow *window, F32 ui_scale_factor, S32 window_width, S32 window_height);
+	virtual BOOL handleWindowDidChangeScreen(LLWindow *window);
 
 	enum DragNDropAction {
 		DNDA_START_TRACKING = 0,// Start tracking an incoming drag
diff --git a/indra/llwindow/llwindowmacosx-objc.h b/indra/llwindow/llwindowmacosx-objc.h
index ef5f803718..743089be6b 100644
--- a/indra/llwindow/llwindowmacosx-objc.h
+++ b/indra/llwindow/llwindowmacosx-objc.h
@@ -147,6 +147,7 @@ void callWindowFocus();
 void callWindowUnfocus();
 void callWindowHide();
 void callWindowUnhide();
+void callWindowDidChangeScreen();
 void callDeltaUpdate(float *delta, unsigned int mask);
 void callMiddleMouseDown(float *pos, unsigned int mask);
 void callMiddleMouseUp(float *pos, unsigned int mask);
diff --git a/indra/llwindow/llwindowmacosx.cpp b/indra/llwindow/llwindowmacosx.cpp
index b02b77ffbd..376b8610b5 100644
--- a/indra/llwindow/llwindowmacosx.cpp
+++ b/indra/llwindow/llwindowmacosx.cpp
@@ -400,6 +400,14 @@ void callWindowUnhide()
 	}
 }
 
+void callWindowDidChangeScreen()
+{
+	if ( gWindowImplementation && gWindowImplementation->getCallbacks() )
+	{
+		gWindowImplementation->getCallbacks()->handleWindowDidChangeScreen(gWindowImplementation);
+	}
+}
+
 void callDeltaUpdate(float *delta, MASK mask)
 {
 	gWindowImplementation->updateMouseDeltas(delta);