Caches the display names in MultiDisplayManager.

ash/system/chromeos/tray_display.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 "ash/system/chromeos/tray_display.h"
 
 #include "ash/display/display_controller.h"
+#include "ash/display/multi_display_manager.h"
 #include "ash/screen_ash.h"
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_delegate.h"
 #include "ash/system/tray/tray_constants.h"
 #include "ash/system/tray/tray_views.h"
 #include "base/utf_string_conversions.h"
 #include "grit/ash_resources.h"
 #include "grit/ash_strings.h"
 #include "ui/aura/display_manager.h"
 #include "ui/aura/env.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/image/image.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/layout/box_layout.h"
 
-#if defined(USE_X11)
-#include "ui/base/x/x11_util.h"
-#endif
-
 namespace ash {
 namespace internal {
 
 class DisplayView : public ash::internal::ActionableView {
  public:
   explicit DisplayView(user::LoginStatus login_status)
       : login_status_(login_status) {
     SetLayoutManager(new
         views::BoxLayout(views::BoxLayout::kHorizontal,
         ash::kTrayPopupPaddingHorizontal, 0,
@@ skipping 13 matching lines @@
   virtual ~DisplayView() {}
 
   void Update() {
     switch (Shell::GetInstance()->output_configurator()->output_state()) {
       case chromeos::STATE_INVALID:
       case chromeos::STATE_HEADLESS:
       case chromeos::STATE_SINGLE:
         SetVisible(false);
         return;
       case chromeos::STATE_DUAL_MIRROR: {
-        // Simply assumes that the primary display appears first and the
-        // secondary display appears next in the list.
-        std::vector<std::string> display_names;
-#if defined(USE_X11)
-        std::vector<XID> output_ids;
-        ui::GetOutputDeviceHandles(&output_ids);
-        display_names = ui::GetDisplayNames(output_ids);
-#endif
-        if (display_names.size() > 1) {
-          label_->SetText(l10n_util::GetStringFUTF16(
-              IDS_ASH_STATUS_TRAY_DISPLAY_MIRRORING,
-              UTF8ToUTF16(display_names[1])));
-          SetVisible(true);
-        } else {
-          SetVisible(false);
-        }
+        label_->SetText(l10n_util::GetStringFUTF16(
+            IDS_ASH_STATUS_TRAY_DISPLAY_MIRRORING, GetExternalDisplayName()));
+        SetVisible(true);
         return;
       }
       case chromeos::STATE_DUAL_PRIMARY_ONLY:
       case chromeos::STATE_DUAL_SECONDARY_ONLY: {
-        aura::DisplayManager* display_manager =
-            aura::Env::GetInstance()->display_manager();
-        if (display_manager->GetNumDisplays() > 1) {
-          label_->SetText(l10n_util::GetStringFUTF16(
-              IDS_ASH_STATUS_TRAY_DISPLAY_EXTENDED,
-              UTF8ToUTF16(display_manager->GetDisplayNameFor(
-                  ScreenAsh::GetSecondaryDisplay()))));
-          SetVisible(true);
-        } else {
-          SetVisible(false);
-        }
+        label_->SetText(l10n_util::GetStringFUTF16(
+            IDS_ASH_STATUS_TRAY_DISPLAY_EXTENDED, GetExternalDisplayName()));
+        SetVisible(true);
         return;
       }
       default:
         NOTREACHED();
     }
   }
 
  private:
+  // Returns the name of the currently connected external display.
+  string16 GetExternalDisplayName() {
+    MultiDisplayManager* display_manager = static_cast<MultiDisplayManager*>(
+        aura::Env::GetInstance()->display_manager());
+
+    gfx::Display external_display(gfx::Display::kInvalidDisplayID);
+    if (display_manager->HasInternalDisplay()) {
+      for (size_t i = 0; i < display_manager->GetNumDisplays(); ++i) {
+        gfx::Display* display = display_manager->GetDisplayAt(i);
+        if (!display_manager->IsInternalDisplayId(display->id())) {
+          external_display = *display;
+          break;
+        }
+      }
+    } else {
+      // Falls back to the secondary display since the system doesn't
+      // distinguish the displays.
+      external_display = ScreenAsh::GetSecondaryDisplay();
+    }
+
+    return UTF8ToUTF16(display_manager->GetDisplayNameFor(external_display));
+  }
+
   // Overridden from ActionableView.
   virtual bool PerformAction(const ui::Event& event) OVERRIDE {
     if (login_status_ == ash::user::LOGGED_IN_USER ||
         login_status_ == ash::user::LOGGED_IN_OWNER ||
         login_status_ == ash::user::LOGGED_IN_GUEST) {
       ash::Shell::GetInstance()->tray_delegate()->ShowDisplaySettings();
     }
 
     return true;
   }
@@ skipping 39 matching lines @@
     default_->Update();
 }
 
 void TrayDisplay::OnDisplayModeChanged() {
   if (default_)
     default_->Update();
 }
 
 }  // namespace internal
 }  // namespace ash