It is time.

ui/base/models/tree_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_TREE_MODEL_H_
-#define UI_BASE_MODELS_TREE_MODEL_H_
-
-#include <vector>
-
-#include "base/strings/string16.h"
-#include "ui/base/ui_base_export.h"
-
-namespace gfx {
-class ImageSkia;
-}
-
-namespace ui {
-
-class TreeModel;
-
-// TreeModelNode --------------------------------------------------------------
-
-// Type of class returned from the model.
-class TreeModelNode {
- public:
-  // Returns the title for the node.
-  virtual const base::string16& GetTitle() const = 0;
-
- protected:
-  virtual ~TreeModelNode() {}
-};
-
-// Observer for the TreeModel. Notified of significant events to the model.
-class UI_BASE_EXPORT TreeModelObserver {
- public:
-  // Notification that nodes were added to the specified parent.
-  virtual void TreeNodesAdded(TreeModel* model,
-                              TreeModelNode* parent,
-                              int start,
-                              int count) = 0;
-
-  // Notification that nodes were removed from the specified parent.
-  virtual void TreeNodesRemoved(TreeModel* model,
-                                TreeModelNode* parent,
-                                int start,
-                                int count) = 0;
-
-  // Notification that the contents of a node has changed.
-  virtual void TreeNodeChanged(TreeModel* model, TreeModelNode* node) = 0;
-
- protected:
-  virtual ~TreeModelObserver() {}
-};
-
-// TreeModel ------------------------------------------------------------------
-
-// The model for TreeView.
-class UI_BASE_EXPORT TreeModel {
- public:
-  // Returns the root of the tree. This may or may not be shown in the tree,
-  // see SetRootShown for details.
-  virtual TreeModelNode* GetRoot() = 0;
-
-  // Returns the number of children in |parent|.
-  virtual int GetChildCount(TreeModelNode* parent) = 0;
-
-  // Returns the child node of |parent| at |index|.
-  virtual TreeModelNode* GetChild(TreeModelNode* parent, int index) = 0;
-
-  // Returns the index of |child| in |parent|.
-  virtual int GetIndexOf(TreeModelNode* parent, TreeModelNode* child) = 0;
-
-  // Returns the parent of |node|, or NULL if |node| is the root.
-  virtual TreeModelNode* GetParent(TreeModelNode* node) = 0;
-
-  // Adds an observer of the model.
-  virtual void AddObserver(TreeModelObserver* observer) = 0;
-
-  // Removes an observer of the model.
-  virtual void RemoveObserver(TreeModelObserver* observer) = 0;
-
-  // Sets the title of |node|.
-  // This is only invoked if the node is editable and the user edits a node.
-  virtual void SetTitle(TreeModelNode* node, const base::string16& title);
-
-  // Returns the set of icons for the nodes in the tree. You only need override
-  // this if you don't want to use the default folder icons.
-  virtual void GetIcons(std::vector<gfx::ImageSkia>* icons) {}
-
-  // Returns the index of the icon to use for |node|. Return -1 to use the
-  // default icon. The index is relative to the list of icons returned from
-  // GetIcons.
-  virtual int GetIconIndex(TreeModelNode* node);
-
- protected:
-  virtual ~TreeModel() {}
-};
-
-}  // namespace ui
-
-#endif  // UI_BASE_MODELS_TREE_MODEL_H_