chrome/browser/ui/sad_tab_helper.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_UI_SAD_TAB_HELPER_H_
   6 #define CHROME_BROWSER_UI_SAD_TAB_HELPER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "content/public/browser/notification_observer.h"
  12 #include "content/public/browser/notification_registrar.h"
  13 #include "content/public/browser/web_contents_observer.h"
  14 #include "content/public/browser/web_contents_user_data.h"
  15
  16 #if defined(OS_MACOSX)
  17 #include "base/mac/foundation_util.h"
  18 #endif
  19
  20 #if defined(OS_MACOSX)
  21 class SadTabController;
  22 #elif defined(TOOLKIT_VIEWS)
  23 namespace views {
  24 class Widget;
  25 }
  26 #elif defined(TOOLKIT_GTK)
  27 class SadTabGtk;
  28 #endif
  29
  30 // Per-tab class to manage sad tab views.
  31 class SadTabHelper : public content::WebContentsObserver,
  32                      public content::NotificationObserver,
  33                      public content::WebContentsUserData<SadTabHelper> {
  34  public:
  35   virtual ~SadTabHelper();
  36
  37   // Platform specific function to determine if there is a current sad tab page.
  38   bool HasSadTab() const;
  39
  40 #if defined(TOOLKIT_VIEWS)
  41   views::Widget* sad_tab() { return sad_tab_.get(); }
  42 #endif
  43
  44  private:
  45   explicit SadTabHelper(content::WebContents* web_contents);
  46   friend class content::WebContentsUserData<SadTabHelper>;
  47
  48   // Platform specific function to get an instance of the sad tab page.
  49   void InstallSadTab(base::TerminationStatus status);
  50
  51   // Overridden from content::WebContentsObserver:
  52   virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;
  53
  54   // Overridden from content::NotificationObserver:
  55   virtual void Observe(int type,
  56                        const content::NotificationSource& source,
  57                        const content::NotificationDetails& details) OVERRIDE;
  58
  59   // Used to get notifications about renderers coming and going.
  60   content::NotificationRegistrar registrar_;
  61
  62   // The platform views used to render the sad tab, non-NULL if visible.
  63 #if defined(OS_MACOSX)
  64   class ScopedPtrRelease {
  65    public:
  66     inline void operator()(void* x) const {
  67       base::mac::NSObjectRelease(x);
  68     }
  69   };
  70   scoped_ptr_malloc<SadTabController, ScopedPtrRelease> sad_tab_;
  71 #elif defined(TOOLKIT_VIEWS)
  72   scoped_ptr<views::Widget> sad_tab_;
  73 #elif defined(TOOLKIT_GTK)
  74   scoped_ptr<SadTabGtk> sad_tab_;
  75 #endif
  76
  77   DISALLOW_COPY_AND_ASSIGN(SadTabHelper);
  78 };
  79
  80 #endif  // CHROME_BROWSER_UI_SAD_TAB_HELPER_H_