1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef UI_BASE_VIEW_PROP_H_
6#define UI_BASE_VIEW_PROP_H_
7
8#include "base/basictypes.h"
9#include "base/memory/ref_counted.h"
10#include "ui/base/ui_base_export.h"
11#include "ui/gfx/native_widget_types.h"
12
13#if !defined(OS_WIN) && !defined(USE_AURA)
14#error view_prop.h is only for windows and aura builds.
15#endif
16
17namespace ui {
18
19// ViewProp maintains a key/value pair for a particular view. ViewProp is
20// designed as a replacement for the Win32's SetProp, but does not make use of
21// window manager memory. ViewProp shares similar semantics as SetProp, the
22// value for a particular view/key pair comes from the last ViewProp created.
23class UI_BASE_EXPORT ViewProp {
24 public:
25  // Associates data with a view/key pair. If a ViewProp has already been
26  // created for the specified pair |data| replaces the current value.
27  //
28  // ViewProp does *not* make a copy of the char*, the pointer is used for
29  // sorting.
30  ViewProp(gfx::AcceleratedWidget view, const char* key, void* data);
31  ~ViewProp();
32
33  // Returns the value associated with the view/key pair, or NULL if there is
34  // none.
35  static void* GetValue(gfx::AcceleratedWidget view, const char* key);
36
37  // Returns the key.
38  const char* Key() const;
39
40 private:
41  class Data;
42
43  // Stores the actual data.
44  scoped_refptr<Data> data_;
45
46  DISALLOW_COPY_AND_ASSIGN(ViewProp);
47};
48
49}  // namespace ui
50
51#endif  // UI_BASE_VIEW_PROP_H_
52