Implement "Language Switcher" for Chromium OS. This change enables users to switch their IME (input method) by clicking a menu button on the status area. Basic structure of the code is almost the same as power_menu_button and power_library.

Demo: http://dev.chromium.org/chromium-os/chromiumos-design-docs/text-input/demos

language_library.{cc,h}: UI-libcros glue. boilerplate code.
language_menu_button.{cc,h}: A button on the status area and its drop-down menu. Implements app/menus/menu_model.h interface.
status_area_view.{cc,h}: Put the language button on the status area.

BUG=494
TEST=Start Chromium OS. Click the menu button on the status area. Then verify that all IMEs you configured (via ibus-setup command, for now) is listed in the drop down menu.

Review URL: http://codereview.chromium.org/449050

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@34540 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 511 insertions, 2 deletions

diff --git a/chrome/browser/chromeos/language_library.cc b/chrome/browser/chromeos/language_library.cc
new file mode 100644
index 0000000..7db0a2b
--- /dev/null
+++ b/chrome/browser/chromeos/language_library.cc
@@ -0,0 +1,100 @@
+// Copyright (c) 2009 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/language_library.h"
+
+#include "base/message_loop.h"
+#include "base/string_util.h"
+#include "chrome/browser/chrome_thread.h"
+#include "chrome/browser/chromeos/cros_library.h"
+
+// Allows InvokeLater without adding refcounting. This class is a Singleton and
+// won't be deleted until it's last InvokeLater is run.
+template <>
+struct RunnableMethodTraits<chromeos::LanguageLibrary> {
+  void RetainCallee(chromeos::LanguageLibrary* obj) {}
+  void ReleaseCallee(chromeos::LanguageLibrary* obj) {}
+};
+
+namespace chromeos {
+
+LanguageLibrary::LanguageLibrary() : language_status_connection_(NULL) {
+  if (EnsureLoaded()) {
+    Init();
+  }
+}
+
+LanguageLibrary::~LanguageLibrary() {
+  if (EnsureLoaded()) {
+    chromeos::DisconnectLanguageStatus(language_status_connection_);
+  }
+}
+
+LanguageLibrary::Observer::~Observer() {
+}
+
+// static
+LanguageLibrary* LanguageLibrary::Get() {
+  return Singleton<LanguageLibrary>::get();
+}
+
+// static
+bool LanguageLibrary::EnsureLoaded() {
+  return CrosLibrary::EnsureLoaded();
+}
+
+void LanguageLibrary::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void LanguageLibrary::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+chromeos::InputLanguageList* LanguageLibrary::GetLanguages() {
+  chromeos::InputLanguageList* result = NULL;
+  if (EnsureLoaded()) {
+    result = chromeos::GetLanguages(language_status_connection_);
+  }
+  return result ? result : CreateFallbackInputLanguageList();
+}
+
+void LanguageLibrary::ChangeLanguage(
+    LanguageCategory category, const std::string& id) {
+  if (EnsureLoaded()) {
+    chromeos::ChangeLanguage(language_status_connection_, category, id.c_str());
+  }
+}
+
+// static
+void LanguageLibrary::LanguageChangedHandler(
+    void* object, const chromeos::InputLanguage& current_language) {
+  LanguageLibrary* language_library = static_cast<LanguageLibrary*>(object);
+  language_library->UpdateCurrentLanguage(current_language);
+}
+
+void LanguageLibrary::Init() {
+  language_status_connection_ = chromeos::MonitorLanguageStatus(
+      &LanguageChangedHandler, this);
+}
+
+void LanguageLibrary::UpdateCurrentLanguage(
+    const chromeos::InputLanguage& current_language) {
+  // Make sure we run on UI thread.
+  if (!ChromeThread::CurrentlyOn(ChromeThread::UI)) {
+    DLOG(INFO) << "UpdateCurrentLanguage (Background thread)";
+    ChromeThread::PostTask(
+        ChromeThread::UI, FROM_HERE,
+        // NewRunnableMethod() copies |current_language| by value.
+        NewRunnableMethod(
+            this, &LanguageLibrary::UpdateCurrentLanguage, current_language));
+    return;
+  }
+
+  DLOG(INFO) << "UpdateCurrentLanguage (UI thread)";
+  current_language_ = current_language;
+  FOR_EACH_OBSERVER(Observer, observers_, LanguageChanged(this));
+}
+
+}  // namespace chromeos
diff --git a/chrome/browser/chromeos/language_library.h b/chrome/browser/chromeos/language_library.h
new file mode 100644
index 0000000..e79d159
--- /dev/null
+++ b/chrome/browser/chromeos/language_library.h
@@ -0,0 +1,86 @@
+// Copyright (c) 2009 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LANGUAGE_LIBRARY_H_
+#define CHROME_BROWSER_CHROMEOS_LANGUAGE_LIBRARY_H_
+
+#include <string>
+
+#include "base/observer_list.h"
+#include "base/singleton.h"
+#include "base/time.h"
+#include "third_party/cros/chromeos_language.h"
+
+namespace chromeos {
+
+// This class handles the interaction with the ChromeOS language library APIs.
+// Classes can add themselves as observers. Users can get an instance of this
+// library class like this: LanguageLibrary::Get()
+class LanguageLibrary {
+ public:
+  class Observer {
+   public:
+    virtual ~Observer() = 0;
+    virtual void LanguageChanged(LanguageLibrary* obj) = 0;
+  };
+
+  // This gets the singleton LanguageLibrary
+  static LanguageLibrary* Get();
+
+  // Makes sure the library is loaded, loading it if necessary. Returns true if
+  // the library has been successfully loaded.
+  static bool EnsureLoaded();
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // Returns the list of IMEs and keyboard layouts we can select. If the cros
+  // library is not found or IBus/DBus daemon is not alive, this function
+  // returns a fallback language list (and never returns NULL).
+  InputLanguageList* GetLanguages();
+
+  // Changes the current IME engine to |id| and enable IME (when |category|
+  // is LANGUAGE_CATEGORY_IME). Changes the current XKB layout to |id| and
+  // disable IME (when |category| is LANGUAGE_CATEGORY_XKB). |id| is a unique
+  // identifier of a IME engine or XKB layout. Please check chromeos_language.h
+  // in src third_party/cros/ for details.
+  void ChangeLanguage(LanguageCategory category, const std::string& id);
+
+  const InputLanguage& current_language() const {
+    return current_language_;
+  }
+
+ private:
+  friend struct DefaultSingletonTraits<LanguageLibrary>;
+
+  LanguageLibrary();
+  ~LanguageLibrary();
+
+  // This method is called when there's a change in language status.
+  // This method is called on a background thread.
+  static void LanguageChangedHandler(
+      void* object, const InputLanguage& current_language);
+
+  // This methods starts the monitoring of language changes.
+  void Init();
+
+  // Called by the handler to update the language status.
+  // This will notify all the Observers.
+  void UpdateCurrentLanguage(const InputLanguage& current_language);
+
+  // A reference to the language api, to allow callbacks when the language
+  // status changes.
+  LanguageStatusConnection* language_status_connection_;
+  ObserverList<Observer> observers_;
+
+  // The language (IME or XKB layout) which currently selected.
+  InputLanguage current_language_;
+
+  DISALLOW_COPY_AND_ASSIGN(LanguageLibrary);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LANGUAGE_LIBRARY_H_
+
diff --git a/chrome/browser/chromeos/language_menu_button.cc b/chrome/browser/chromeos/language_menu_button.cc
new file mode 100644
index 0000000..87092cc
--- /dev/null
+++ b/chrome/browser/chromeos/language_menu_button.cc
@@ -0,0 +1,241 @@
+// Copyright (c) 2009 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/language_menu_button.h"
+
+#include <string>
+
+#include "app/l10n_util.h"
+#include "app/resource_bundle.h"
+#include "base/time.h"
+#include "chrome/browser/browser.h"
+#include "grit/generated_resources.h"
+#include "grit/theme_resources.h"
+
+namespace {
+
+const int kRadioGroupNone = 0;
+const int kRadioGroupLanguage = 1;
+const size_t kMaxLanguageNameLen = 7;
+const wchar_t kSpacer[] = L"MMMMMMM";
+
+// Returns true if the |index| points to the "Configure IME" menu item.
+bool IsIndexShowControlPanel(
+    int index, chromeos::InputLanguageList* language_list) {
+  DCHECK_GE(index, 0);
+  if (language_list->empty()) {
+    // If language_list is empty, then there's no separator. So "Configure IME"
+    // should be at index 0.
+    DCHECK_EQ(index, 0);
+    return index == 0;
+  }
+  return static_cast<size_t>(index) == (language_list->size() + 1);
+}
+
+// Converts chromeos::InputLanguage object into human readable string. Returns
+// a string for the drop-down menu if |for_menu| is true. Otherwise, returns a
+// string for the status area.
+std::string FormatInputLanguage(
+    const chromeos::InputLanguage& language, bool for_menu) {
+  std::string formatted = language.display_name;
+  if (formatted.empty()) {
+    formatted = language.id;
+  }
+  if (for_menu) {
+    switch (language.category) {
+      case chromeos::LANGUAGE_CATEGORY_XKB:
+        // TODO(yusukes): Use message catalog.
+        formatted += " (Layout)";
+        break;
+      case chromeos::LANGUAGE_CATEGORY_IME:
+        // TODO(yusukes): Use message catalog.
+        formatted += " (IME)";
+        break;
+    }
+  } else {
+    // For status area. Trim the string.
+    formatted = formatted.substr(0, kMaxLanguageNameLen);
+    // TODO(yusukes): Simple substr() does not work for non-ASCII string.
+    // TODO(yusukes): How can we ensure that the trimmed string does not
+    // overflow the area?
+  }
+  return formatted;
+}
+
+}  // namespace
+
+namespace chromeos {
+
+////////////////////////////////////////////////////////////////////////////////
+// LanguageMenuButton
+
+LanguageMenuButton::LanguageMenuButton(Browser* browser)
+    : MenuButton(NULL, std::wstring(), this, false),
+      language_list_(LanguageLibrary::Get()->GetLanguages()),
+      // Since the constructor of |language_menu_| calls this->GetItemCount(),
+      // we have to initialize |language_list_| before hand.
+      ALLOW_THIS_IN_INITIALIZER_LIST(language_menu_(this)),
+      browser_(browser) {
+  DCHECK(language_list_.get() && !language_list_->empty());
+  // Grab the real estate.
+  UpdateIcon(kSpacer);
+  // Display the default XKB name (usually "US").
+  const std::string name = FormatInputLanguage(language_list_->at(0), false);
+  UpdateIcon(UTF8ToWide(name));
+  LanguageLibrary::Get()->AddObserver(this);
+}
+
+LanguageMenuButton::~LanguageMenuButton() {
+  LanguageLibrary::Get()->RemoveObserver(this);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// LanguageMenuButton, menus::MenuModel implementation:
+
+int LanguageMenuButton::GetCommandIdAt(int index) const {
+  return index;  // dummy
+}
+
+bool LanguageMenuButton::IsLabelDynamicAt(int index) const {
+  // Menu content for the language button could change time by time.
+  return true;
+}
+
+bool LanguageMenuButton::GetAcceleratorAt(
+    int index, menus::Accelerator* accelerator) const {
+  // Views for Chromium OS does not support accelerators yet.
+  return false;
+}
+
+bool LanguageMenuButton::IsItemCheckedAt(int index) const {
+  DCHECK_GE(index, 0);
+  DCHECK(language_list_.get());
+  if (static_cast<size_t>(index) < language_list_->size()) {
+    const InputLanguage& language = language_list_->at(index);
+    return language == LanguageLibrary::Get()->current_language();
+  }
+  return false;
+}
+
+int LanguageMenuButton::GetGroupIdAt(int index) const {
+  DCHECK_GE(index, 0);
+  DCHECK(language_list_.get());
+  if (static_cast<size_t>(index) < language_list_->size()) {
+    return kRadioGroupLanguage;
+  }
+  return kRadioGroupNone;
+}
+
+bool LanguageMenuButton::HasIcons() const  {
+  // TODO(yusukes): Display IME icons.
+  return false;
+}
+
+bool LanguageMenuButton::GetIconAt(int index, SkBitmap* icon) const {
+  return false;
+}
+
+bool LanguageMenuButton::IsEnabledAt(int index) const {
+  // Just return true so all IMEs and XLB layouts listed could be clicked.
+  return true;
+}
+
+menus::MenuModel* LanguageMenuButton::GetSubmenuModelAt(int index) const {
+  return NULL;
+}
+
+void LanguageMenuButton::HighlightChangedTo(int index) {
+  // Views for Chromium OS does not support this interface yet.
+}
+
+void LanguageMenuButton::MenuWillShow() {
+  // Views for Chromium OS does not support this interface yet.
+}
+
+int LanguageMenuButton::GetItemCount() const {
+  DCHECK(language_list_.get());
+  if (language_list_->empty()) {
+    return 1;  // no separator; "Configure IME" only
+  }
+  return language_list_->size() + 2;  // separator + "Configure IME"
+}
+
+menus::MenuModel::ItemType LanguageMenuButton::GetTypeAt(int index) const {
+  DCHECK_GE(index, 0);
+  DCHECK(language_list_.get());
+  if (IsIndexShowControlPanel(index, language_list_.get())) {
+    return menus::MenuModel::TYPE_COMMAND;  // "Configure IME"
+  }
+  if (static_cast<size_t>(index) < language_list_->size()) {
+    return menus::MenuModel::TYPE_RADIO;
+  }
+
+  DCHECK_EQ(static_cast<size_t>(index), language_list_->size());
+  return menus::MenuModel::TYPE_SEPARATOR;
+}
+
+string16 LanguageMenuButton::GetLabelAt(int index) const {
+  DCHECK_GE(index, 0);
+  DCHECK(language_list_.get());
+  if (IsIndexShowControlPanel(index, language_list_.get())) {
+    // TODO(yusukes): Use message catalog.
+    return WideToUTF16(L"Configure IME...");
+  }
+  if (static_cast<size_t>(index) < language_list_->size()) {
+    std::string name = FormatInputLanguage(language_list_->at(index), true);
+    return UTF8ToUTF16(name);
+  }
+  NOTREACHED();
+  return WideToUTF16(L"");
+}
+
+void LanguageMenuButton::ActivatedAt(int index) {
+  DCHECK_GE(index, 0);
+  DCHECK(language_list_.get());
+  if (IsIndexShowControlPanel(index, language_list_.get())) {
+    browser_->ShowControlPanel();
+    return;
+  }
+  if (static_cast<size_t>(index) < language_list_->size()) {
+    const InputLanguage& language = language_list_->at(index);
+    LanguageLibrary::Get()->ChangeLanguage(language.category, language.id);
+    return;
+  }
+  NOTREACHED();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// LanguageMenuButton, views::ViewMenuDelegate implementation:
+
+void LanguageMenuButton::RunMenu(views::View* source, const gfx::Point& pt) {
+  language_list_.reset(LanguageLibrary::Get()->GetLanguages());
+  language_menu_.Rebuild();
+  language_menu_.UpdateStates();
+  language_menu_.RunMenuAt(pt, views::Menu2::ALIGN_TOPRIGHT);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// LanguageMenuButton, PowerLibrary::Observer implementation:
+
+void LanguageMenuButton::LanguageChanged(LanguageLibrary* obj) {
+  const std::string name = FormatInputLanguage(obj->current_language(), false);
+  UpdateIcon(UTF8ToWide(name));
+}
+
+void LanguageMenuButton::UpdateIcon(const std::wstring& name) {
+  set_border(NULL);
+  SetFont(ResourceBundle::GetSharedInstance().GetFont(
+      ResourceBundle::BaseFont).DeriveFont(0, gfx::Font::BOLD));
+  SetEnabledColor(SK_ColorWHITE);
+  SetShowHighlighted(false);
+  SetText(name);
+  // TODO(yusukes): Show icon on the status area?
+  set_alignment(TextButton::ALIGN_RIGHT);
+  SchedulePaint();
+}
+
+// TODO(yusukes): Register and handle hotkeys for IME and XKB switching?
+
+}  // namespace chromeos
+
diff --git a/chrome/browser/chromeos/language_menu_button.h b/chrome/browser/chromeos/language_menu_button.h
new file mode 100644
index 0000000..f1ebfbc
--- /dev/null
+++ b/chrome/browser/chromeos/language_menu_button.h
@@ -0,0 +1,69 @@
+// Copyright (c) 2006-2008 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_LANGUAGE_MENU_BUTTON_H_
+#define CHROME_BROWSER_CHROMEOS_LANGUAGE_MENU_BUTTON_H_
+
+#include "chrome/browser/chromeos/language_library.h"
+#include "chrome/browser/chromeos/status_area_button.h"
+#include "views/controls/menu/menu_2.h"
+#include "views/controls/menu/view_menu_delegate.h"
+
+class Browser;
+class SkBitmap;
+
+namespace chromeos {
+
+// The language menu button in the status area.
+// This class will handle getting the IME/XKB status and populating the menu.
+class LanguageMenuButton : public views::MenuButton,
+                           public views::ViewMenuDelegate,
+                           public menus::MenuModel,
+                           public LanguageLibrary::Observer {
+ public:
+  explicit LanguageMenuButton(Browser* browser);
+  virtual ~LanguageMenuButton();
+
+  // views::Menu2Model implementation.
+  virtual bool HasIcons() const;
+  virtual int GetItemCount() const;
+  virtual menus::MenuModel::ItemType GetTypeAt(int index) const;
+  virtual int GetCommandIdAt(int index) const;
+  virtual string16 GetLabelAt(int index) const;
+  virtual bool IsLabelDynamicAt(int index) const;
+  virtual bool GetAcceleratorAt(int index,
+                                menus::Accelerator* accelerator) const;
+  virtual bool IsItemCheckedAt(int index) const;
+  virtual int GetGroupIdAt(int index) const;
+  virtual bool GetIconAt(int index, SkBitmap* icon) const;
+  virtual bool IsEnabledAt(int index) const;
+  virtual menus::MenuModel* GetSubmenuModelAt(int index) const;
+  virtual void HighlightChangedTo(int index);
+  virtual void ActivatedAt(int index);
+  virtual void MenuWillShow();
+
+  // LanguageLibrary::Observer implementation.
+  virtual void LanguageChanged(LanguageLibrary* obj);
+
+ private:
+  // views::ViewMenuDelegate implementation.
+  virtual void RunMenu(views::View* source, const gfx::Point& pt);
+
+  // Update the status area with |name|.
+  void UpdateIcon(const std::wstring& name);
+
+  // The current language list.
+  scoped_ptr<InputLanguageList> language_list_;
+
+  // The language menu.
+  views::Menu2 language_menu_;
+  // The browser window that owns us.
+  Browser* browser_;
+
+  DISALLOW_COPY_AND_ASSIGN(LanguageMenuButton);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_LANGUAGE_MENU_BUTTON_H_
diff --git a/chrome/browser/chromeos/status_area_view.cc b/chrome/browser/chromeos/status_area_view.cc
index f3ba39d..bb58e11 100755
--- a/chrome/browser/chromeos/status_area_view.cc
+++ b/chrome/browser/chromeos/status_area_view.cc
@@ -14,6 +14,7 @@
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_window.h"
 #include "chrome/browser/chromeos/clock_menu_button.h"
+#include "chrome/browser/chromeos/language_menu_button.h"
 #include "chrome/browser/chromeos/network_menu_button.h"
 #include "chrome/browser/chromeos/power_menu_button.h"
 #include "chrome/browser/chromeos/status_area_button.h"
@@ -37,6 +38,9 @@ namespace chromeos {
 const int kLeftBorder = 1;
 // Number of pixels to separate the clock from the next item on the right.
 const int kClockSeparation = 4;
+// Number of pixels to separate the language selector from the next item
+// on the right.
+const int kLanguageSeparation = 4;
 
 // BrowserWindowGtk tiles its image with this offset
 const int kCustomFrameBackgroundVerticalOffset = 15;
@@ -126,6 +130,7 @@ StatusAreaView::StatusAreaView(Browser* browser,
     : browser_(browser),
       window_(window),
       clock_view_(NULL),
+      language_view_(NULL),
       network_view_(NULL),
       battery_view_(NULL),
       menu_view_(NULL) {
@@ -134,6 +139,10 @@ StatusAreaView::StatusAreaView(Browser* browser,
 void StatusAreaView::Init() {
   ThemeProvider* theme = browser_->profile()->GetThemeProvider();
 
+  // Language.
+  language_view_ = new LanguageMenuButton(browser_);
+  AddChildView(language_view_);
+
   // Clock.
   clock_view_ = new ClockMenuButton(browser_);
   AddChildView(clock_view_);
@@ -164,7 +173,7 @@ void StatusAreaView::Update() {
 
 gfx::Size StatusAreaView::GetPreferredSize() {
   // Start with padding.
-  int result_w = kLeftBorder + kClockSeparation;
+  int result_w = kLeftBorder + kClockSeparation + kLanguageSeparation;
   int result_h = 0;
   for (int i = 0; i < GetChildViewCount(); i++) {
     views::View* cur = GetChildViewAt(i);
@@ -195,9 +204,11 @@ void StatusAreaView::Layout() {
 
       cur_x += cur_size.width();
 
-      // Buttons have built in padding, but clock doesn't.
+      // Buttons have built in padding, but clock and language status don't.
       if (cur == clock_view_)
         cur_x += kClockSeparation;
+      else if (cur == language_view_)
+        cur_x += kLanguageSeparation;
     }
   }
 }
diff --git a/chrome/browser/chromeos/status_area_view.h b/chrome/browser/chromeos/status_area_view.h
index 95cfdf6..ee3a172 100644
--- a/chrome/browser/chromeos/status_area_view.h
+++ b/chrome/browser/chromeos/status_area_view.h
@@ -17,6 +17,7 @@ class Browser;
 namespace chromeos {
 
 class ClockMenuButton;
+class LanguageMenuButton;
 class NetworkMenuButton;
 class PowerMenuButton;
 class StatusAreaButton;
@@ -73,6 +74,7 @@ class StatusAreaView : public views::View,
   gfx::NativeWindow window_;
 
   ClockMenuButton* clock_view_;
+  LanguageMenuButton* language_view_;
   NetworkMenuButton* network_view_;
   PowerMenuButton* battery_view_;
   StatusAreaButton* menu_view_;