ash: First pass of Applist v2.

ash/app_list/pagination_model.h

+// Copyright (c) 2012 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_APP_LIST_PAGINATION_MODEL_H_
+#define ASH_APP_LIST_PAGINATION_MODEL_H_
+#pragma once
+
+#include "ash/ash_export.h"
+#include "base/basictypes.h"
+#include "base/observer_list.h"
+
+namespace ash {
+
+class PaginationModelObserver;
+
+// A simple pagination model that consists of two numbers: the total pages and
+// the currently selected page. The model is a single selection model that at
+// the most one page can become selected at any time.
+class ASH_EXPORT PaginationModel {
+ public:
+  PaginationModel();
+  ~PaginationModel();
+
+  void SetTotalPages(int total_pages);
+  void SelectPage(int page);
+
+  void AddObserver(PaginationModelObserver* observer);
+  void RemoveObserver(PaginationModelObserver* observer);
+
+  int total_pages() const {
+    return total_pages_;
+  }
+
+  int selected_page() const {
+    return selected_page_;
+  }
+
+ private:
+  int total_pages_;
+  int selected_page_;
+  ObserverList<PaginationModelObserver> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(PaginationModel);
+};
+
+}  // namespace ash
+
+#endif  // ASH_APP_LIST_PAGINATION_MODEL_H_