It is time.

ui/base/models/list_selection_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 UI_BASE_MODELS_LIST_SELECTION_MODEL_H_
-#define UI_BASE_MODELS_LIST_SELECTION_MODEL_H_
-
-#include <vector>
-
-#include "base/basictypes.h"
-#include "ui/base/ui_base_export.h"
-
-namespace ui {
-
-// Selection model represented as a list of ints. Used by the TabStrip. In
-// addition to the set of selected indices ListSelectionModel maintains the
-// following:
-// active: the index of the currently visible tab in the tab strip.
-// anchor: the index of the last tab the user clicked on. Extending the
-// selection extends it from this index.
-//
-// Typically there is only one selected item, in which case the anchor and
-// active index correspond to the same thing.
-class UI_BASE_EXPORT ListSelectionModel {
- public:
-  typedef std::vector<int> SelectedIndices;
-
-  // Used to identify no selection.
-  static const int kUnselectedIndex;
-
-  ListSelectionModel();
-  ~ListSelectionModel();
-
-  // See class description for details of the anchor.
-  void set_anchor(int anchor) { anchor_ = anchor; }
-  int anchor() const { return anchor_; }
-
-  // See class description for details of active.
-  void set_active(int active) { active_ = active; }
-  int active() const { return active_; }
-
-  // True if nothing is selected.
-  bool empty() const { return selected_indices_.empty(); }
-
-  // Number of selected indices.
-  size_t size() const { return selected_indices_.size(); }
-
-  // Increments all indices >= |index|. For example, if the selection consists
-  // of [0, 1, 5] and this is invoked with 1, it results in [0, 2, 6]. This also
-  // updates the anchor and active indices.
-  // This is used when a new tab is inserted into the tabstrip.
-  void IncrementFrom(int index);
-
-  // Shifts all indices > |index| down by 1. If |index| is selected, it is
-  // removed. For example, if the selection consists of [0, 1, 5] and this is
-  // invoked with 1, it results in [0, 4]. This is used when a tab is removed
-  // from the tabstrip.
-  void DecrementFrom(int index);
-
-  // Sets the anchor, active and selection to |index|.
-  void SetSelectedIndex(int index);
-
-  // Returns true if |index| is selected.
-  bool IsSelected(int index) const;
-
-  // Adds |index| to the selection. This does not change the active or anchor
-  // indices.
-  void AddIndexToSelection(int index);
-
-  // Removes |index| from the selection. This does not change the active or
-  // anchor indices.
-  void RemoveIndexFromSelection(int index);
-
-  // Extends the selection from the anchor to |index|. If the anchor is empty,
-  // this sets the anchor, selection and active indices to |index|.
-  void SetSelectionFromAnchorTo(int index);
-
-  // Makes sure the indices from the anchor to |index| are selected. This only
-  // adds to the selection.
-  void AddSelectionFromAnchorTo(int index);
-
-  // Invoked when an item moves. |from| is the original index, and |to| the
-  // target index.
-  // NOTE: this matches the TabStripModel API. If moving to a greater index,
-  // |to| should be the index *after* removing |from|. For example, consider
-  // three tabs 'A B C', to move A to the end of the list, this should be
-  // invoked with '0, 2'.
-  void Move(int from, int to);
-
-  // Sets the anchor and active to kUnselectedIndex, and removes all the
-  // selected indices.
-  void Clear();
-
-  // Returns the selected indices. The selection is always ordered in acending
-  // order.
-  const SelectedIndices& selected_indices() const { return selected_indices_; }
-
-  // Copies the selection from |source| to this.
-  void Copy(const ListSelectionModel& source);
-
-  // Compares this selection with |rhs|.
-  bool Equals(const ListSelectionModel& rhs) const;
-
- private:
-  SelectedIndices selected_indices_;
-
-  int active_;
-
-  int anchor_;
-
-  DISALLOW_COPY_AND_ASSIGN(ListSelectionModel);
-};
-
-}  // namespace ui
-
-#endif  // UI_BASE_MODELS_LIST_SELECTION_MODEL_H_