MonitorManager to manage multiple monitors.

ui/aura/monitor_manager.cc

Index: ui/aura/monitor_manager.cc
diff --git a/ui/aura/monitor_manager.cc b/ui/aura/monitor_manager.cc
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+++ b/ui/aura/monitor_manager.cc
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+// 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 "ui/aura/monitor_manager.h"
+
+#include "base/basictypes.h"
+#include "base/stl_util.h"
+#include "ui/aura/monitor.h"
+#include "ui/aura/root_window.h"
+#include "ui/aura/window.h"
+#include "ui/aura/window_observer.h"
+#include "ui/gfx/rect.h"
+
+namespace aura {
+namespace {
+
+// A monitor manager assuming there is one monitor.
+class SingleMonitorManager : public MonitorManager,
+                             public WindowObserver {
+ public:
+  SingleMonitorManager(RootWindow* root_window)
+      : root_window_(root_window),
+        monitor_(new Monitor()) {
+    root_window_->AddObserver(this);
+    Update(root_window_->bounds().size());
+  }
+
+  virtual ~SingleMonitorManager() {
+    if (root_window_)
+      root_window_->RemoveObserver(this);
+  }
+
+  // MonitorManager overrides:
+  virtual const Monitor* GetMonitorNearestWindow(const Window* window) const {
+    return monitor_.get();
+  }
+  virtual const Monitor* GetMonitorNearestPoint(const gfx::Point& point) const {
+    return monitor_.get();
+  }
+  virtual const Monitor* GetPrimaryMonitor() const {
+    return monitor_.get();
+  }
+  virtual size_t GetNumMonitors() const {
+    return 1;
+  }
+  virtual Monitor* GetMonitorNearestWindow(const Window* window) {
+    return monitor_.get();
+  }
+
+  // WindowObserver overrides:
+  virtual void OnWindowBoundsChanged(Window* window, const gfx::Rect& bounds)
+      OVERRIDE {
+    Update(bounds.size());
+  }
+  virtual void OnWindowDestroying(Window* window) {
+    if (root_window_ == window)
+      root_window_ = NULL;
+  }
+
+ private:
+  void Update(const gfx::Size size) {
+    gfx::Rect new_bounds(size);
+    monitor_->set_bounds(new_bounds);
+  }
+
+  RootWindow* root_window_;
+  scoped_ptr<Monitor> monitor_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingleMonitorManager);
+};
+
+}  // namespace
+
+MonitorManager::MonitorManager() {
+}
+
+MonitorManager::~MonitorManager() {
+}
+
+// static
+MonitorManager* CreateSingleMonitorManager(RootWindow* root_window) {
+  return new SingleMonitorManager(root_window);
+}
+
+}  // namespace aura