Give page/app menu native menu bar feel....

chrome/browser/gtk/browser_toolbar_gtk.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/gtk/browser_toolbar_gtk.h"
 
 #include <gdk/gdkkeysyms.h>
 #include <X11/XF86keysym.h>
 
 #include "app/l10n_util.h"
@@ skipping 136 matching lines @@
   gtk_box_pack_start(GTK_BOX(omnibox_hbox_), go_->widget(), FALSE, FALSE, 0);
 
   gtk_box_pack_start(GTK_BOX(toolbar_), omnibox_hbox_, TRUE, TRUE, 0);
 
   // Group the menu buttons together in an hbox.
   GtkWidget* menus_hbox_ = gtk_hbox_new(FALSE, 0);
   GtkWidget* page_menu = BuildToolbarMenuButton(IDR_MENU_PAGE,
       l10n_util::GetStringUTF8(IDS_PAGEMENU_TOOLTIP),
       &page_menu_button_);
   page_menu_.reset(new MenuGtk(this, GetStandardPageMenu(), accel_group_));
+  g_signal_connect(page_menu_->widget(), "motion-notify-event",
+                   G_CALLBACK(OnPageAppMenuMouseMotion), this);
+  g_signal_connect(page_menu_->widget(), "move-current",
+                   G_CALLBACK(OnPageAppMenuMoveCurrent), this);
   gtk_box_pack_start(GTK_BOX(menus_hbox_), page_menu, FALSE, FALSE, 0);
 
   GtkWidget* chrome_menu = BuildToolbarMenuButton(IDR_MENU_CHROME,
       l10n_util::GetStringFUTF8(IDS_APPMENU_TOOLTIP,
           WideToUTF16(l10n_util::GetString(IDS_PRODUCT_NAME))),
       &app_menu_button_);
   app_menu_.reset(new MenuGtk(this, GetStandardAppMenu(), accel_group_));
+  g_signal_connect(app_menu_->widget(), "motion-notify-event",
+                   G_CALLBACK(OnPageAppMenuMouseMotion), this);
+  g_signal_connect(app_menu_->widget(), "move-current",
+                   G_CALLBACK(OnPageAppMenuMoveCurrent), this);
   gtk_box_pack_start(GTK_BOX(menus_hbox_), chrome_menu, FALSE, FALSE, 0);
 
   gtk_box_pack_start(GTK_BOX(toolbar_), menus_hbox_, FALSE, FALSE, 0);
 
   // Force all the CustomDrawButtons to load the correct rendering style.
   UserChangedTheme();
 
   gtk_widget_show_all(toolbar_);
 
   if (show_home_button_.GetValue()) {
@@ skipping 196 matching lines @@
   gtk_drag_dest_set(home_->widget(), GTK_DEST_DEFAULT_ALL,
                     NULL, 0, GDK_ACTION_COPY);
   GtkDndUtil::SetDestTargetListFromCodeMask(home_->widget(),
                                             GtkDndUtil::X_CHROME_TEXT_PLAIN |
                                             GtkDndUtil::X_CHROME_TEXT_URI_LIST);
 
   g_signal_connect(home_->widget(), "drag-data-received",
                    G_CALLBACK(OnDragDataReceived), this);
 }
 
+void BrowserToolbarGtk::ChangeActiveMenu(GtkWidget* active_menu,
+    guint timestamp) {
+  MenuGtk* old_menu;
+  MenuGtk* new_menu;
+  GtkWidget* relevant_button;
+  if (active_menu == app_menu_->widget()) {
+    old_menu = app_menu_.get();
+    new_menu = page_menu_.get();
+    relevant_button = page_menu_button_.get();
+  } else {
+    old_menu = page_menu_.get();
+    new_menu = app_menu_.get();
+    relevant_button = app_menu_button_.get();
+  }
+
+  old_menu->Cancel();
+  gtk_chrome_button_set_paint_state(GTK_CHROME_BUTTON(relevant_button),
+                                    GTK_STATE_ACTIVE);
+  new_menu->Popup(relevant_button, 0, timestamp);
+}
+
 // static
 gboolean BrowserToolbarGtk::OnToolbarExpose(GtkWidget* widget,
                                             GdkEventExpose* e,
                                             BrowserToolbarGtk* toolbar) {
   cairo_t* cr = gdk_cairo_create(GDK_DRAWABLE(widget->window));
   cairo_rectangle(cr, e->area.x, e->area.y, e->area.width, e->area.height);
   cairo_clip(cr);
   // The toolbar is supposed to blend in with the active tab, so we have to pass
   // coordinates for the IDR_THEME_TOOLBAR bitmap relative to the top of the
   // tab strip.
@@ skipping 64 matching lines @@
 
   bool url_is_newtab = url.spec() == chrome::kChromeUINewTabURL;
   toolbar->profile_->GetPrefs()->SetBoolean(prefs::kHomePageIsNewTabPage,
                                             url_is_newtab);
   if (!url_is_newtab) {
     toolbar->profile_->GetPrefs()->SetString(prefs::kHomePage,
                                              UTF8ToWide(url.spec()));
   }
 }
 
+// static
+gboolean BrowserToolbarGtk::OnPageAppMenuMouseMotion(GtkWidget* menu,
+    GdkEventMotion* event, BrowserToolbarGtk* toolbar) {
+  if (gtk_util::WidgetContainsCursor(menu == toolbar->app_menu_->widget() ?
+                                     toolbar->page_menu_button_.get() :
+                                     toolbar->app_menu_button_.get())) {
+    toolbar->ChangeActiveMenu(menu, event->time);
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+// static
+void BrowserToolbarGtk::OnPageAppMenuMoveCurrent(GtkWidget* menu,
+    GtkMenuDirectionType dir, BrowserToolbarGtk* toolbar) {
+  GtkWidget* active_item = GTK_MENU_SHELL(menu)->active_menu_item;
+
+  switch (dir) {
+    case GTK_MENU_DIR_CHILD:
+      // The move is going to open a submenu; don't override default behavior.
+      if (active_item && gtk_menu_item_get_submenu(GTK_MENU_ITEM(active_item)))
+        break;
+      // Fall through.
+    case GTK_MENU_DIR_PARENT:
+      toolbar->ChangeActiveMenu(menu, gtk_get_current_event_time());
+      // This signal doesn't have a return value; we have to manually stop its
+      // propagation.
+      g_signal_stop_emission_by_name(menu, "move-current");
+    default:
+      break;
+  }
+}
+
 void BrowserToolbarGtk::InitNineBox() {
   // TODO(estade): use |profile_|?
   background_ninebox_.reset(new NineBox(
       browser_->profile()->GetThemeProvider(),
       0, IDR_THEME_TOOLBAR, 0, 0, 0, 0, 0, 0, 0));
 }