ash uber tray: Allow customizing each item depending on whether the user is logged in or not.

chrome/browser/chromeos/system/ash_system_tray_delegate.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/chromeos/system/ash_system_tray_delegate.h"
 
 #include "ash/shell.h"
 #include "ash/system/audio/audio_controller.h"
 #include "ash/system/brightness/brightness_controller.h"
 #include "ash/system/power/power_status_controller.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "base/logging.h"
 #include "chrome/browser/chromeos/audio/audio_handler.h"
 #include "chrome/browser/chromeos/dbus/dbus_thread_manager.h"
 #include "chrome/browser/chromeos/dbus/power_manager_client.h"
 #include "chrome/browser/chromeos/login/user.h"
 #include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_list.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_service.h"
 
 namespace chromeos {
 
 namespace {
 
 class SystemTrayDelegate : public ash::SystemTrayDelegate,
                            public AudioHandler::VolumeObserver,
-                           public PowerManagerClient::Observer {
+                           public PowerManagerClient::Observer,
+                           public content::NotificationObserver {
  public:
   explicit SystemTrayDelegate(ash::SystemTray* tray) : tray_(tray) {
     AudioHandler::GetInstance()->AddVolumeObserver(this);
     DBusThreadManager::Get()->GetPowerManagerClient()->AddObserver(this);
     DBusThreadManager::Get()->GetPowerManagerClient()->RequestStatusUpdate(
         PowerManagerClient::UPDATE_USER);
+
+    registrar_.Add(this,
+                   chrome::NOTIFICATION_LOGIN_USER_CHANGED,
+                   content::NotificationService::AllSources());
   }
 
   virtual ~SystemTrayDelegate() {
     AudioHandler* audiohandler = AudioHandler::GetInstance();
     if (audiohandler)
       audiohandler->RemoveVolumeObserver(this);
     DBusThreadManager::Get()->GetPowerManagerClient()->RemoveObserver(this);
   }
 
   // Overridden from ash::SystemTrayDelegate.
   virtual const std::string GetUserDisplayName() OVERRIDE {
     return UserManager::Get()->logged_in_user().GetDisplayName();
   }
 
   virtual const std::string GetUserEmail() OVERRIDE {
     return UserManager::Get()->logged_in_user().email();
   }
 
   virtual const SkBitmap& GetUserImage() OVERRIDE {
     return UserManager::Get()->logged_in_user().image();
   }
 
+  virtual ash::user::LoginStatus GetUserLoginStatus() OVERRIDE {
+    UserManager* manager = UserManager::Get();
+    if (!manager->user_is_logged_in())
+      return ash::user::LOGGED_IN_NONE;
+    if (manager->current_user_is_owner())
+      return ash::user::LOGGED_IN_OWNER;
+    if (manager->IsLoggedInAsGuest())
+      return ash::user::LOGGED_IN_GUEST;
+    return ash::user::LOGGED_IN_USER;
+  }
+
   virtual void ShowSettings() OVERRIDE {
     BrowserList::GetLastActive()->OpenOptionsDialog();
   }
 
   virtual void ShowHelp() OVERRIDE {
     BrowserList::GetLastActive()->ShowHelpTab();
   }
 
   virtual bool IsAudioMuted() const OVERRIDE {
     return AudioHandler::GetInstance()->IsMuted();
@@ skipping 18 matching lines @@
   virtual void SignOut() OVERRIDE {
     BrowserList::AttemptUserExit();
   }
 
   virtual void LockScreen() OVERRIDE {
     DBusThreadManager::Get()->GetPowerManagerClient()->
         NotifyScreenLockRequested();
   }
 
  private:
-  ash::SystemTray* tray_;
-
   // Overridden from AudioHandler::VolumeObserver.
   virtual void OnVolumeChanged() OVERRIDE {
     float level = AudioHandler::GetInstance()->GetVolumePercent() / 100.f;
     ash::Shell::GetInstance()->audio_controller()->
         OnVolumeChanged(level);
   }
 
   // Overridden from PowerManagerClient::Observer.
   virtual void BrightnessChanged(int level, bool user_initiated) OVERRIDE {
     ash::Shell::GetInstance()->brightness_controller()->
         OnBrightnessChanged(level / 100.f, user_initiated);
   }
 
   virtual void PowerChanged(const PowerSupplyStatus& power_status) OVERRIDE {
     ash::Shell::GetInstance()->power_status_controller()->
         OnPowerStatusChanged(power_status);
   }
 
   // TODO(sad): Override more from PowerManagerClient::Observer here (e.g.
   // PowerButtonStateChanged etc.).
 
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE {
+    switch (type) {
+      case chrome::NOTIFICATION_LOGIN_USER_CHANGED: {
+        tray_->UpdateAfterLoginStatusChange(GetUserLoginStatus());
+        break;
+      }
+      default:
+        NOTREACHED();
+    }
+  }
+
+  ash::SystemTray* tray_;
+  content::NotificationRegistrar registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(SystemTrayDelegate);
 };
 
 }  // namespace
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate(ash::SystemTray* tray) {
   return new chromeos::SystemTrayDelegate(tray);
 }
 
 }  // namespace chromeos