chrome/browser/chromeos/input_method/browser_state_monitor.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/chromeos/input_method/browser_state_monitor.h"
   6
   7 #include "base/logging.h"
   8 #include "chrome/browser/chrome_notification_types.h"
   9 #include "chrome/browser/chromeos/input_method/input_method_util.h"
  10 #include "content/public/browser/notification_service.h"
  11 #include "ui/base/ime/chromeos/input_method_delegate.h"
  12
  13 namespace chromeos {
  14 namespace input_method {
  15
  16 BrowserStateMonitor::BrowserStateMonitor(
  17     const base::Callback<void(InputMethodManager::UISessionState)>& observer)
  18     : observer_(observer), ui_session_(InputMethodManager::STATE_LOGIN_SCREEN) {
  19   notification_registrar_.Add(this,
  20                               chrome::NOTIFICATION_LOGIN_USER_CHANGED,
  21                               content::NotificationService::AllSources());
  22   notification_registrar_.Add(this,
  23                               chrome::NOTIFICATION_SESSION_STARTED,
  24                               content::NotificationService::AllSources());
  25   notification_registrar_.Add(this,
  26                               chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED,
  27                               content::NotificationService::AllSources());
  28   // We should not use ALL_BROWSERS_CLOSING here since logout might be cancelled
  29   // by JavaScript after ALL_BROWSERS_CLOSING is sent (crosbug.com/11055).
  30   notification_registrar_.Add(this,
  31                               chrome::NOTIFICATION_APP_TERMINATING,
  32                               content::NotificationService::AllSources());
  33
  34   if (!observer_.is_null())
  35     observer_.Run(ui_session_);
  36 }
  37
  38 BrowserStateMonitor::~BrowserStateMonitor() {
  39 }
  40
  41 void BrowserStateMonitor::Observe(
  42     int type,
  43     const content::NotificationSource& source,
  44     const content::NotificationDetails& details) {
  45   const InputMethodManager::UISessionState old_ui_session = ui_session_;
  46   switch (type) {
  47     case chrome::NOTIFICATION_APP_TERMINATING: {
  48       ui_session_ = InputMethodManager::STATE_TERMINATING;
  49       break;
  50     }
  51     case chrome::NOTIFICATION_LOGIN_USER_CHANGED: {
  52       // The user logged in, but the browser window for user session is not yet
  53       // ready. An initial input method hasn't been set to the manager.
  54       // Note that the notification is also sent when Chrome crashes/restarts
  55       // as of writing, but it might be changed in the future (therefore we need
  56       // to listen to NOTIFICATION_SESSION_STARTED as well.)
  57       DVLOG(1) << "Received chrome::NOTIFICATION_LOGIN_USER_CHANGED";
  58       ui_session_ = InputMethodManager::STATE_BROWSER_SCREEN;
  59       break;
  60     }
  61     case chrome::NOTIFICATION_SESSION_STARTED: {
  62       // The user logged in, and the browser window for user session is ready.
  63       // An initial input method has already been set.
  64       // We should NOT call InitializePrefMembers() here since the notification
  65       // is sent in the PreProfileInit phase in case when Chrome crashes and
  66       // restarts.
  67       DVLOG(1) << "Received chrome::NOTIFICATION_SESSION_STARTED";
  68       ui_session_ = InputMethodManager::STATE_BROWSER_SCREEN;
  69       break;
  70     }
  71     case chrome::NOTIFICATION_SCREEN_LOCK_STATE_CHANGED: {
  72       const bool is_screen_locked = *content::Details<bool>(details).ptr();
  73       ui_session_ = is_screen_locked ? InputMethodManager::STATE_LOCK_SCREEN
  74                                      : InputMethodManager::STATE_BROWSER_SCREEN;
  75       break;
  76     }
  77     default: {
  78       NOTREACHED();
  79       break;
  80     }
  81   }
  82
  83   if (old_ui_session != ui_session_ && !observer_.is_null())
  84     observer_.Run(ui_session_);
  85
  86   // Note: browser notifications are sent in the following order.
  87   //
  88   // Normal login:
  89   // 1. chrome::NOTIFICATION_LOGIN_USER_CHANGED is sent.
  90   // 2. Preferences::NotifyPrefChanged() is called. preload_engines (which
  91   //    might change the current input method) and current/previous input method
  92   //    are sent to the manager.
  93   // 3. chrome::NOTIFICATION_SESSION_STARTED is sent.
  94   //
  95   // Chrome crash/restart (after logging in):
  96   // 1. chrome::NOTIFICATION_LOGIN_USER_CHANGED might be sent.
  97   // 2. chrome::NOTIFICATION_SESSION_STARTED is sent.
  98   // 3. Preferences::NotifyPrefChanged() is called. The same things as above
  99   //    happen.
 100   //
 101   // We have to be careful not to overwrite both local and user prefs when
 102   // preloaded engine is set. Note that it does not work to do nothing in
 103   // InputMethodChanged() between chrome::NOTIFICATION_LOGIN_USER_CHANGED and
 104   // chrome::NOTIFICATION_SESSION_STARTED because SESSION_STARTED is sent very
 105   // early on Chrome crash/restart.
 106 }
 107
 108 }  // namespace input_method
 109 }  // namespace chromeos