[Aura] Implement views-based applist.

ui/aura_shell/app_list/app_list_model.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 UI_AURA_SHELL_APP_LIST_APP_LIST_MODEL_H_
+#define UI_AURA_SHELL_APP_LIST_APP_LIST_MODEL_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "ui/aura_shell/app_list/app_list_item_group_model.h"
+#include "ui/aura_shell/aura_shell_export.h"
+#include "ui/base/models/list_model.h"
+
+namespace aura_shell {
+
+// Model for AppListView. It is consisted of a list of AppListItemGroupModels,
+// which in turn owns a list of AppListItemModels.
+class AURA_SHELL_EXPORT AppListModel {
+ public:
+  AppListModel();
+  virtual ~AppListModel();
+
+  void AddGroup(AppListItemGroupModel* group);
+  AppListItemGroupModel* GetGroup(int index);
+
+  void AddObserver(ui::ListModelObserver* observer);
+  void RemoveObserver(ui::ListModelObserver* observer);
+
+  int group_count() const {
+    return groups_.item_count();
+  }
+
+ private:
+  ui::ListModel<AppListItemGroupModel> groups_;
+
+  DISALLOW_COPY_AND_ASSIGN(AppListModel);
+};
+
+}  // namespace aura_shell
+
+#endif  // UI_AURA_SHELL_APP_LIST_APP_LIST_MODEL_H_