Integrate the Spelling service to Chrome.

chrome/browser/tab_contents/render_view_context_menu_observer.h

+// Copyright (c) 2011 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_TAB_CONTENTS_RENDER_VIEW_CONTEXT_MENU_OBSERVER_H_
+#define CHROME_BROWSER_TAB_CONTENTS_RENDER_VIEW_CONTEXT_MENU_OBSERVER_H_
+#pragma once
+
+struct ContextMenuParams;
+
+// The interface used for implementing context-menu items. The following
+// instruction describe how to implement a context-menu item with this
+// interface.
+//
+// 1. Add command IDs for the context-menu items to 'chrome_command_ids.h'.
+//
+//   #define IDC_MY_COMMAND 99999
+//
+// 2. Add strings for the context-menu items to 'generated_sources.grd'.
+//
+//   <message name="IDS_MY_COMMAND" desc="...">
+//     My command
+//   </message>
+//
+// 3. Create a class that implements this interface. (It is a good idea to use
+// the RenderViewContextMenuDelegate interface to avoid accessing the
+// RenderViewContetMenu class directly.)

[Avi (use Gerrit), 2011/08/23 18:38:19]

typo in class name

[Hironori Bono, 2011/08/25 11:18:58]

Done.

+//
+//  class MyMenuObserver : public RenderViewContextMenuObserver {
+//   public:
+//    MyMenuObserver(RenderViewContextMenuDelegate* d);
+//    ~MyMenuObserver();
+//
+//    virtual void InitMenu(const ContextMenuParams& params) OVERRIDE;
+//    virtual bool IsCommandIdSupported(int command_id) OVERRIDE;
+//    virtual bool IsCommandIdEnabled(int command_id) OVERRIDE;
+//    virtual void ExecuteCommand(int command_id) OVERRIDE;
+//
+//   private:
+//    RenderViewContextMenuDelgate* delegate_;
+//  }
+//
+//  void MyMenuObserver::InitMenu(const ContextMenuParams& params) {
+//    delegate_->AddMenuItem(IDC_MY_COMMAND,...);
+//  }
+//
+//  bool MyMenuObserver::IsCommandIdSupported(int command_id) {
+//    return command_id == IDC_MY_COMMAND;
+//  }
+//
+//  bool MyMenuObserver::IsCommandIdEnabled(int command_id) {
+//    DCHECK(command_id == IDC_MY_COMMAND);
+//    return true;
+//  }
+//
+//  void MyMenuObserver::ExecuteCommand(int command_id) {
+//    DCHECK(command_id == IDC_MY_COMMAND);
+//  }
+//
+// 4. Add this observer class to the RenderViewContextMenu class. (It is good
+// to use scoped_ptr<> so Chrome can create its instances only when it needs.)
+//
+//  class RenderViewContextMenu {
+//    ...
+//   private:
+//    scoped_ptr<MyMenuObserver> my_menu_observer_;
+//  };
+//
+// 5. Create its instance in InitMenu() and add it to the observer list of the
+// RenderViewContextMenu class.
+//
+//  void RenderViewContextMenu::InitMenu() {
+//    ...
+//    my_menu_observer_.reset(new MyMenuObserver(this));
+//    observers_.AddObserver(my_menu_observer_.get());
+//  }
+//
+//
+class RenderViewContextMenuObserver {
+ public:
+  virtual ~RenderViewContextMenuObserver() {}
+
+  // Called when the RenderViewContextMenu class initializes a context menu. We
+  // usually call RenderViewContextMenuDelegate::AddMenuItem() to add menu items
+  // in this function.
+  virtual void InitMenu(const ContextMenuParams& params);
+
+  // Called when the RenderViewContextMenu class asks whether an observer
+  // listens the specified command ID. If this function returns true, the

[Avi (use Gerrit), 2011/08/23 18:38:19]

listens for the specified...

[Hironori Bono, 2011/08/25 11:18:58]

Done.

+  // RenderViewContextMenu class calls IsCommandIdEnabled() or ExecuteCommand().
+  virtual bool IsCommandIdSupported(int command_id);
+
+  // Called when the RenderViewContextMenu class sets the initial status of the
+  // specified context-menu item. If we need to enable or disable a context-menu
+  // item while showing, use RenderViewContextMenuDelegate::UpdateMenuItem().
+  virtual bool IsCommandIdEnabled(int command_id);
+
+  // Called when a user selects the specified context-menu item.
+  virtual void ExecuteCommand(int command_id);
+};
+
+#endif  // CHROME_BROWSER_TAB_CONTENTS_RENDER_VIEW_CONTEXT_MENU_OBSERVER_H_