Implement "Language Switcher" for Chromium OS.

chrome/browser/chromeos/language_menu_button.cc

+// 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
+