autocomplete_accessibility.h revision 3345a6884c488ff3a535c2c9acdd33d74b37e311 
1// Copyright (c) 2006-2008 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 CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_ACCESSIBILITY_H_
6#define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_ACCESSIBILITY_H_
7#pragma once
8
9#include <atlbase.h>
10#include <atlcom.h>
11#include <oleacc.h>
12
13#include "base/basictypes.h"
14#include "base/scoped_comptr_win.h"
15
16class AutocompleteEditViewWin;
17
18////////////////////////////////////////////////////////////////////////////////
19//
20// AutocompleteAccessibility
21//
22// Class implementing the MSAA IAccessible COM interface for
23// AutocompleteEditViewWin, providing accessibility to be used by screen
24// readers and other assistive technology (AT).
25//
26////////////////////////////////////////////////////////////////////////////////
27class ATL_NO_VTABLE AutocompleteAccessibility
28  : public CComObjectRootEx<CComMultiThreadModel>,
29    public IDispatchImpl<IAccessible, &IID_IAccessible, &LIBID_Accessibility> {
30 public:
31  BEGIN_COM_MAP(AutocompleteAccessibility)
32    COM_INTERFACE_ENTRY2(IDispatch, IAccessible)
33    COM_INTERFACE_ENTRY(IAccessible)
34  END_COM_MAP()
35
36  AutocompleteAccessibility() {}
37  ~AutocompleteAccessibility() {}
38
39  HRESULT Initialize(const AutocompleteEditViewWin* edit_box);
40
41  // Supported IAccessible methods.
42
43  // Retrieves the number of accessible children.
44  STDMETHODIMP get_accChildCount(LONG* child_count);
45
46  // Retrieves an IDispatch interface pointer for the specified child.
47  STDMETHODIMP get_accChild(VARIANT var_child, IDispatch** disp_child);
48
49  // Retrieves the IDispatch interface of the object's parent.
50  STDMETHODIMP get_accParent(IDispatch** disp_parent);
51
52  // Traverses to another UI element and retrieves the object.
53  STDMETHODIMP accNavigate(LONG nav_dir, VARIANT start, VARIANT* end);
54
55  // Retrieves the object that has the keyboard focus.
56  STDMETHODIMP get_accFocus(VARIANT* focus_child);
57
58  // Retrieves the name of the specified object.
59  STDMETHODIMP get_accName(VARIANT var_id, BSTR* name);
60
61  // Retrieves the tooltip description.
62  STDMETHODIMP get_accDescription(VARIANT var_id, BSTR* desc);
63
64  // Returns the current value of the edit box.
65  STDMETHODIMP get_accValue(VARIANT var_id, BSTR* value);
66
67  // Retrieves the current state of the specified object.
68  STDMETHODIMP get_accState(VARIANT var_id, VARIANT* state);
69
70  // Retrieves information describing the role of the specified object.
71  STDMETHODIMP get_accRole(VARIANT var_id, VARIANT* role);
72
73  // Retrieves a string that describes the object's default action.
74  STDMETHODIMP get_accDefaultAction(VARIANT var_id, BSTR* default_action);
75
76  // Retrieves the specified object's current screen location.
77  STDMETHODIMP accLocation(LONG* x_left, LONG* y_top, LONG* width, LONG* height,
78                           VARIANT var_id);
79
80  // Retrieves the child element or child object at a given point on the screen.
81  STDMETHODIMP accHitTest(LONG x_left, LONG y_top, VARIANT* child);
82
83  // Retrieves the specified object's shortcut.
84  STDMETHODIMP get_accKeyboardShortcut(VARIANT var_id, BSTR* access_key);
85
86  // Non-supported IAccessible methods.
87
88  // Out-dated and can be safely said to be very rarely used.
89  STDMETHODIMP accDoDefaultAction(VARIANT var_id);
90
91  // Selections not applicable to views.
92  STDMETHODIMP get_accSelection(VARIANT* selected);
93  STDMETHODIMP accSelect(LONG flags_sel, VARIANT var_id);
94
95  // Help functions not supported.
96  STDMETHODIMP get_accHelp(VARIANT var_id, BSTR* help);
97  STDMETHODIMP get_accHelpTopic(BSTR* help_file, VARIANT var_id,
98                                LONG* topic_id);
99
100  // Deprecated functions, not implemented here.
101  STDMETHODIMP put_accName(VARIANT var_id, BSTR put_name);
102  STDMETHODIMP put_accValue(VARIANT var_id, BSTR put_val);
103
104 protected:
105  // A pointer containing the Windows' default IAccessible implementation for
106  // this object. Used where it is acceptable to return default MSAA
107  // information.
108  ScopedComPtr<IAccessible> default_accessibility_server_;
109
110 private:
111  const AutocompleteEditViewWin* edit_box_;
112
113  DISALLOW_COPY_AND_ASSIGN(AutocompleteAccessibility);
114};
115
116#endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_ACCESSIBILITY_H_
117