diff --git a/redo/window_darwin.go b/redo/window_darwin.go
index c3d4521..be9ceec 100644
--- a/redo/window_darwin.go
+++ b/redo/window_darwin.go
@@ -4,6 +4,7 @@ package ui
 
 import (
 	"unsafe"
+"fmt"
 )
 
 // #include "objc_darwin.h"
@@ -123,7 +124,13 @@ func windowClosing(xw unsafe.Pointer) C.BOOL {
 	}
 	return C.NO
 }
-	
+
+//export windowResized
+func windowResized(xw unsafe.Pointer, width C.uintptr_t, height C.uintptr_t) {
+	w := (*window)(unsafe.Pointer(xw))
+_=w//TODO
+	fmt.Printf("new size %d x %d\n", width, height)
+}
 
 // TODO for testing
 func newButton(string) *Request { return nil }
diff --git a/redo/window_darwin.m b/redo/window_darwin.m
index d0b1347..426f353 100644
--- a/redo/window_darwin.m
+++ b/redo/window_darwin.m
@@ -20,6 +20,16 @@
 	return windowClosing(self->gowin);
 }
 
+- (void)windowDidResize:(NSNotification *)n
+{
+	NSWindow *w;
+	NSRect r;
+
+	w = toNSWindow([n object]);
+	r = [[w contentView] frame];
+	windowResized(self->gowin, (uintptr_t) r.size.width, (uintptr_t) r.size.height);
+}
+
 @end
 
 id newWindow(intptr_t width, intptr_t height)