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;
+
+// LauncherItemDelegateManager helps Launcher/LauncherView to choose right
+// LauncherItemDelegate based on LauncherItemType.
+// When new LauncherItemDelegate is created, it must be registered by
+// RegisterLauncherItemDelegate(). If not, Launcher/LauncherView can't get
+// LauncherItem's LauncherItemDelegate.
+// TODO(simon.hong81): This class should own all LauncherItemDelegate.
+class ASH_EXPORT LauncherItemDelegateManager {
+ public:
+  LauncherItemDelegateManager();
+  virtual ~LauncherItemDelegateManager();
+
+  // Returns LauncherItemDelegate for |item_type|.
+  // This class doesn't own each LauncherItemDelegate for now.
+  LauncherItemDelegate* GetLauncherItemDelegate(
+      ash::LauncherItemType item_type);
+
+  // Register |item_delegate| for |type|.
+  // For now, This class doesn't own |item_delegate|.
+  // TODO(simon.hong81): Register LauncherItemDelegate with LauncherID.
+  void RegisterLauncherItemDelegate(
+      ash::LauncherItemType type, LauncherItemDelegate* item_delegate);
+
+ 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_