chrome/browser/ui/sad_tab_helper.h

// 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.

#ifndef CHROME_BROWSER_UI_SAD_TAB_HELPER_H_
#define CHROME_BROWSER_UI_SAD_TAB_HELPER_H_

#include "base/basictypes.h"
#include "base/compiler_specific.h"
#include "base/memory/scoped_ptr.h"
#include "content/public/browser/notification_observer.h"
#include "content/public/browser/notification_registrar.h"
#include "content/public/browser/web_contents_observer.h"
#include "content/public/browser/web_contents_user_data.h"

namespace chrome {
class SadTab;
}

#if defined(TOOLKIT_VIEWS)
namespace views {
class Widget;
}
#endif

// Per-tab class to manage sad tab views.
class SadTabHelper : public content::WebContentsObserver,
                     public content::NotificationObserver,
                     public content::WebContentsUserData<SadTabHelper> {
 public:
  virtual ~SadTabHelper();

#if defined(TOOLKIT_VIEWS)
  views::Widget* sad_tab() { return sad_tab_.get(); }
#endif

 private:
  friend class content::WebContentsUserData<SadTabHelper>;

  explicit SadTabHelper(content::WebContents* web_contents);

  void InstallSadTab(base::TerminationStatus status);

  // Overridden from content::WebContentsObserver:
  virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;

  // Overridden from content::NotificationObserver:
  virtual void Observe(int type,
                       const content::NotificationSource& source,
                       const content::NotificationDetails& details) OVERRIDE;

  // Used to get notifications about renderers coming and going.
  content::NotificationRegistrar registrar_;

#if defined(TOOLKIT_VIEWS)
  scoped_ptr<views::Widget> sad_tab_;
#elif defined(TOOLKIT_GTK) || defined(OS_MACOSX)
  scoped_ptr<chrome::SadTab> sad_tab_;
#endif

  DISALLOW_COPY_AND_ASSIGN(SadTabHelper);
};

#endif  // CHROME_BROWSER_UI_SAD_TAB_HELPER_H_