Refactor LauncherDelegate

ash/launcher/launcher_item_delegate_manager.h

+// Copyright 2013 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 ASH_LAUNCHER_LAUNCHER_ITEM_DELEGATE_MANAGER_H_
+#define ASH_LAUNCHER_LAUNCHER_ITEM_DELEGATE_MANAGER_H_
+
+#include <map>
+
+#include "ash/ash_export.h"
+#include "ash/launcher/launcher_types.h"
+#include "base/compiler_specific.h"
+
+namespace ash {
+class LauncherItemDelegate;
+
+class ASH_EXPORT LauncherItemDelegateManager {

[sky, 2013/08/27 00:03:47]

Add a description.

[simonhong_, 2013/08/27 01:05:29]

Done.

+ public:
+  LauncherItemDelegateManager();
+  virtual ~LauncherItemDelegateManager();
+
+  // Returns LauncherItemDelegate for |item_type|.

[sky, 2013/08/27 00:03:47]

Document ownership.

[simonhong_, 2013/08/27 01:05:29]

Done.

+  LauncherItemDelegate* GetLauncherItemDelegate(
+      ash::LauncherItemType item_type);
+
+  // Register |item_delegate| for |type|.
+  void RegisterLauncherItemDelegate(

[sky, 2013/08/27 00:03:47]

Document ownership. I think in the long term I would like to see this class take
ownership of the LauncherItemDelegate, ownership is clearer that way.

Wouldn't it be better if we register per id?

[simonhong_, 2013/08/27 01:05:29]

Yes, I think so.
This needs some refactoring of LauncherItemController and
ChromeLauncherController.
I'll add it my todo list.
Yes, registering with id is more better.
Todo this, some works are needed in ChromeLauncherController.
It will be achieved by registering LauncherItemDelegate when LauncherItem is
created and added.
(I added it in my todo list, too)

+      ash::LauncherItemType type, LauncherItemDelegate* item_delegate);
+
+  // Unregister LauncherItemDelegate for |type|.
+  void UnregisterLauncherItemDelegate(ash::LauncherItemType type);
+
+ private:
+  typedef std::map<ash::LauncherItemType, LauncherItemDelegate*>
+      LauncherItemTypeToItemDelegateMap;
+
+  LauncherItemTypeToItemDelegateMap item_type_to_item_delegate_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(LauncherItemDelegateManager);
+};
+
+}  // namespace ash
+
+#endif  // ASH_LAUNCHER_LAUNCHER_ITEM_DELEGATE_MANAGER_H_