Swap main menu with app-specific menu when app window focused.

chrome/browser/app_controller_mac.mm

Index: chrome/browser/app_controller_mac.mm
diff --git a/chrome/browser/app_controller_mac.mm b/chrome/browser/app_controller_mac.mm
index 703ae1648e4900d6be38f73505195ab0ec2a9d22..ba9b67a014a7dbb439e35edf0adca4b3010a5e57 100644
--- a/chrome/browser/app_controller_mac.mm
+++ b/chrome/browser/app_controller_mac.mm
@@ -4,6 +4,7 @@
 
 #import "chrome/browser/app_controller_mac.h"
 
+#include "apps/shell_window.h"
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/command_line.h"
@@ -26,6 +27,7 @@
 #include "chrome/browser/download/download_service_factory.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
+#include "chrome/browser/extensions/shell_window_registry.h"
 #include "chrome/browser/first_run/first_run.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/printing/print_dialog_cloud.h"
@@ -68,6 +70,7 @@
 #include "chrome/common/chrome_paths_internal.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/cloud_print/cloud_print_class_mac.h"
+#include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/mac/app_mode_common.h"
 #include "chrome/common/pref_names.h"
@@ -192,6 +195,7 @@ void RecordLastRunAppBundlePath() {
 - (BOOL)shouldQuitWithInProgressDownloads;
 - (void)executeApplication:(id)sender;
 - (void)profileWasRemoved:(const base::FilePath&)profilePath;
+- (void)showOrHideMenuItemsForPackagedApp:(NSNotification*)notification;
 @end
 
 class AppControllerProfileObserver : public ProfileInfoCacheObserver {
@@ -307,6 +311,12 @@ class AppControllerProfileObserver : public ProfileInfoCacheObserver {
   // Set up the command updater for when there are no windows open
   [self initMenuState];
 
+  [[NSNotificationCenter defaultCenter]
+      addObserver:self
+         selector:@selector(showOrHideMenuItemsForPackagedApp:)
+             name:NSWindowDidBecomeMainNotification
+           object:nil];
+
   // Initialize the Profile menu.
   [self initProfileMenu];
 }
@@ -1377,6 +1387,52 @@ class AppControllerProfileObserver : public ProfileInfoCacheObserver {
       WorkAreaChanged());
 }
 
+// If the window is an app window, show the menu bar for that app, otherwise
+// restore the Chrome menu bar.
+- (void)showOrHideMenuItemsForPackagedApp:(NSNotification*)notification {
+  NSMenu* mainMenu = [NSApp mainMenu];
+  apps::ShellWindow* shellWindow =
+      extensions::ShellWindowRegistry::GetShellWindowForNativeWindowAnyProfile(
+          [notification object]);
+
+  if (!shellWindow) {
+    if (!appMenuItem_)
+      return;
+
+    [mainMenu removeItem:appMenuItem_];
+    appMenuItem_.reset();
+
+    // Restore the Chrome main menu bar.
+    for (NSMenuItem* item in [mainMenu itemArray])
+      [item setHidden:NO];
+
+    return;
+  }
+
+  const extensions::Extension* app = shellWindow->extension();
+  NSString* appId = base::SysUTF8ToNSString(app->id());
+  NSString* title = base::SysUTF8ToNSString(app->name());
+
+  if (appMenuItem_) {
+    if ([[appMenuItem_ title] isEqualToString:appId])
+      return;
+
+    [mainMenu removeItem:appMenuItem_];
+  }
+
+  // Hide everything and add a menu item for the app.
+  for (NSMenuItem* item in [mainMenu itemArray])
+    [item setHidden:YES];

[Nico, 2013/07/19 19:43:05]

nit: This could be in an else to the previous if, right?

[jackhou1, 2013/07/21 23:46:12]

Done.

+
+  appMenuItem_.reset(
+      [[NSMenuItem alloc] initWithTitle:appId
+                                 action:nil
+                          keyEquivalent:@""]);
+  base::scoped_nsobject<NSMenu> appMenu([[NSMenu alloc] initWithTitle:title]);

[Nico, 2013/07/19 19:43:05]

Is the plan that apps can have their own menu entries?

[jackhou1, 2013/07/21 23:46:12]

I'm planning to add Quit, Hide, and Show to this menu. I don't think it's been
decided if apps will be able to define custom entries (or additional menus), but
if that goes ahead, this code will probably either move out of here, or talk to
some interface that provides the menus.

+  [appMenuItem_ setSubmenu:appMenu];
+  [mainMenu addItem:appMenuItem_];
+}
+
 @end  // @implementation AppController
 
 //---------------------------------------------------------------------------