MacViews: Intercept events for Menus (after AppKit has interpreted keystrokes)

ui/views/cocoa/native_widget_mac_nswindow.mm

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ui/views/cocoa/native_widget_mac_nswindow.h"
 
 #include "base/mac/foundation_util.h"
 #import "ui/views/cocoa/views_nswindow_delegate.h"
+#include "ui/views/controls/menu/menu_controller.h"
 #include "ui/views/widget/native_widget_mac.h"
 
 @interface NativeWidgetMacNSWindow ()
 - (ViewsNSWindowDelegate*)viewsNSWindowDelegate;
 - (views::Widget*)viewsWidget;
+- (BOOL)hasViewsMenuActive;
 @end
 
 @implementation NativeWidgetMacNSWindow
 
 - (ViewsNSWindowDelegate*)viewsNSWindowDelegate {
   return base::mac::ObjCCastStrict<ViewsNSWindowDelegate>([self delegate]);
 }
 
 - (views::Widget*)viewsWidget {
   return [[self viewsNSWindowDelegate] nativeWidgetMac]->GetWidget();
 }
 
+- (BOOL)hasViewsMenuActive {
+  views::MenuController* menuController =
+      views::MenuController::GetActiveInstance();
+  return menuController && menuController->owner() == [self viewsWidget];
+}
+
 // Ignore [super canBecome{Key,Main}Window]. The default is NO for windows with
 // NSBorderlessWindowMask, which is not the desired behavior.
 // Note these can be called via -[NSWindow close] while the widget is being torn
 // down, so check for a delegate.
 - (BOOL)canBecomeKeyWindow {
   return [self delegate] && [self viewsWidget]->CanActivate();
 }
 
 - (BOOL)canBecomeMainWindow {
   return [self delegate] && [self viewsWidget]->CanActivate();
 }
 
+// Override sendEvent to allow key events to be forwarded to a toolkit-views
+// menu while it is active, and while still allowing the native subview to
+// retain firstResponder status.
+- (void)sendEvent:(NSEvent*)event {
+  NSEventType type = [event type];
+  if ((type != NSKeyDown && type != NSKeyUp) || ![self hasViewsMenuActive]) {
+    [super sendEvent:event];
+    return;
+  }
+
+  // Send to the menu, after converting the event into an action message using
+  // the content view.
+  if (type == NSKeyDown)
+    [[self contentView] keyDown:event];
+  else
+    [[self contentView] keyUp:event];
+}
+
 // Override display, since this is the first opportunity Cocoa gives to detect
 // a visibility change in some cases. For example, restoring from the dock first
 // calls -[NSWindow display] before any NSWindowDelegate functions and before
 // ordering the window (and without actually calling -[NSWindow deminiaturize]).
 // By notifying the delegate that a display is about to occur, it can apply a
 // correct visibility state, before [super display] requests a draw of the
 // contentView. -[NSWindow isVisible] can still report NO at this point, so this
 // gives the delegate time to apply correct visibility before the draw occurs.
 - (void)display {
   [[self viewsNSWindowDelegate] onWindowWillDisplay];
   [super display];
 }
 
 // Override window order functions to intercept other visibility changes. This
 // is needed in addition to the -[NSWindow display] override because Cocoa
 // hardly ever calls display, and reports -[NSWindow isVisible] incorrectly
 // when ordering in a window for the first time.
 - (void)orderWindow:(NSWindowOrderingMode)orderingMode
          relativeTo:(NSInteger)otherWindowNumber {
   [[self viewsNSWindowDelegate] onWindowOrderWillChange:orderingMode];
   [super orderWindow:orderingMode relativeTo:otherWindowNumber];
   [[self viewsNSWindowDelegate] onWindowOrderChanged:nil];
 }
 
 @end