Home | History | Annotate | Download | only in autocomplete 
      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 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/win/scoped_comptr.h"
     15 
     16 class 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 ////////////////////////////////////////////////////////////////////////////////
     27 class 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   base::win::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