Use Widget frame and WidgetDelegate in ActvityWidget

athena/activity/activity_widget_delegate.h

+// Copyright 2014 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 ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_
+#define ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_
+
+#include "base/macros.h"
+#include "ui/views/widget/widget_delegate.h"
+
+namespace athena {
+class ActivityViewModel;
+
+// A default WidgetDelegate for activities.
+// TODO(oshima): Allow AcitivyViewModel to create custom WidgetDelegate.
+class ActivityWidgetDelegate : public views::WidgetDelegate {
+ public:
+  explicit ActivityWidgetDelegate(ActivityViewModel* view_model);
+  virtual ~ActivityWidgetDelegate();
+
+  // views::WidgetDelegate:
+  virtual base::string16 GetWindowTitle() const OVERRIDE;
+  virtual void DeleteDelegate() OVERRIDE;
+  virtual views::Widget* GetWidget() OVERRIDE;
+  virtual const views::Widget* GetWidget() const OVERRIDE;
+  virtual views::View* GetContentsView() OVERRIDE;
+  virtual views::ClientView* CreateClientView(views::Widget* widget) OVERRIDE;
+  virtual views::NonClientFrameView* CreateNonClientFrameView(
+      views::Widget* widget) OVERRIDE;
+
+ private:
+  ActivityViewModel* view_model_;
+
+  DISALLOW_COPY_AND_ASSIGN(ActivityWidgetDelegate);
+};
+
+}  // namespace athena
+
+#endif  // ATHENA_ACTIVITY_ACTIVITY_WIDGET_DELEGATE_H_