1 /*
2 * Copyright (C) 2008, 2009, 2010 Apple Inc. All Rights Reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27 #include "AccessibilityController.h"
28
29 #include "AccessibilityUIElement.h"
30 #include "DumpRenderTree.h"
31 #include "FrameLoadDelegate.h"
32 #include <JavaScriptCore/Assertions.h>
33 #include <JavaScriptCore/JSRetainPtr.h>
34 #include <JavaScriptCore/JSStringRef.h>
35 #include <WebCore/COMPtr.h>
36 #include <WebKit/WebKit.h>
37 #include <oleacc.h>
38 #include <string>
39
40 using namespace std;
41
AccessibilityController()42 AccessibilityController::AccessibilityController()
43 : m_focusEventHook(0)
44 , m_scrollingStartEventHook(0)
45 , m_valueChangeEventHook(0)
46 , m_allEventsHook(0)
47 {
48 }
49
~AccessibilityController()50 AccessibilityController::~AccessibilityController()
51 {
52 setLogFocusEvents(false);
53 setLogValueChangeEvents(false);
54
55 if (m_allEventsHook)
56 UnhookWinEvent(m_allEventsHook);
57
58 for (HashMap<PlatformUIElement, JSObjectRef>::iterator it = m_notificationListeners.begin(); it != m_notificationListeners.end(); ++it)
59 JSValueUnprotect(frame->globalContext(), it->second);
60 }
61
elementAtPoint(int x,int y)62 AccessibilityUIElement AccessibilityController::elementAtPoint(int x, int y)
63 {
64 // FIXME: implement
65 return 0;
66 }
67
focusedElement()68 AccessibilityUIElement AccessibilityController::focusedElement()
69 {
70 COMPtr<IAccessible> rootAccessible = rootElement().platformUIElement();
71
72 VARIANT vFocus;
73 if (FAILED(rootAccessible->get_accFocus(&vFocus)))
74 return 0;
75
76 if (V_VT(&vFocus) == VT_I4) {
77 ASSERT(V_I4(&vFocus) == CHILDID_SELF);
78 // The root accessible object is the focused object.
79 return rootAccessible;
80 }
81
82 ASSERT(V_VT(&vFocus) == VT_DISPATCH);
83 // We have an IDispatch; query for IAccessible.
84 return COMPtr<IAccessible>(Query, V_DISPATCH(&vFocus));
85 }
86
rootElement()87 AccessibilityUIElement AccessibilityController::rootElement()
88 {
89 COMPtr<IWebView> view;
90 if (FAILED(frame->webView(&view)))
91 return 0;
92
93 COMPtr<IWebViewPrivate> viewPrivate(Query, view);
94 if (!viewPrivate)
95 return 0;
96
97 HWND webViewWindow;
98 if (FAILED(viewPrivate->viewWindow((OLE_HANDLE*)&webViewWindow)))
99 return 0;
100
101 // Get the root accessible object by querying for the accessible object for the
102 // WebView's window.
103 COMPtr<IAccessible> rootAccessible;
104 if (FAILED(AccessibleObjectFromWindow(webViewWindow, static_cast<DWORD>(OBJID_CLIENT), __uuidof(IAccessible), reinterpret_cast<void**>(&rootAccessible))))
105 return 0;
106
107 return rootAccessible;
108 }
109
logEventProc(HWINEVENTHOOK,DWORD event,HWND hwnd,LONG idObject,LONG idChild,DWORD,DWORD)110 static void CALLBACK logEventProc(HWINEVENTHOOK, DWORD event, HWND hwnd, LONG idObject, LONG idChild, DWORD, DWORD)
111 {
112 // Get the accessible object for this event.
113 COMPtr<IAccessible> parentObject;
114
115 VARIANT vChild;
116 VariantInit(&vChild);
117
118 HRESULT hr = AccessibleObjectFromEvent(hwnd, idObject, idChild, &parentObject, &vChild);
119 ASSERT(SUCCEEDED(hr));
120
121 // Get the name of the focused element, and log it to stdout.
122 BSTR nameBSTR;
123 hr = parentObject->get_accName(vChild, &nameBSTR);
124 ASSERT(SUCCEEDED(hr));
125 wstring name(nameBSTR, ::SysStringLen(nameBSTR));
126 SysFreeString(nameBSTR);
127
128 switch (event) {
129 case EVENT_OBJECT_FOCUS:
130 printf("Received focus event for object '%S'.\n", name.c_str());
131 break;
132
133 case EVENT_OBJECT_VALUECHANGE: {
134 BSTR valueBSTR;
135 hr = parentObject->get_accValue(vChild, &valueBSTR);
136 ASSERT(SUCCEEDED(hr));
137 wstring value(valueBSTR, ::SysStringLen(valueBSTR));
138 SysFreeString(valueBSTR);
139
140 printf("Received value change event for object '%S', value '%S'.\n", name.c_str(), value.c_str());
141 break;
142 }
143
144 case EVENT_SYSTEM_SCROLLINGSTART:
145 printf("Received scrolling start event for object '%S'.\n", name.c_str());
146 break;
147
148 default:
149 printf("Received unknown event for object '%S'.\n", name.c_str());
150 break;
151 }
152
153 VariantClear(&vChild);
154 }
155
setLogFocusEvents(bool logFocusEvents)156 void AccessibilityController::setLogFocusEvents(bool logFocusEvents)
157 {
158 if (!!m_focusEventHook == logFocusEvents)
159 return;
160
161 if (!logFocusEvents) {
162 UnhookWinEvent(m_focusEventHook);
163 m_focusEventHook = 0;
164 return;
165 }
166
167 // Ensure that accessibility is initialized for the WebView by querying for
168 // the root accessible object.
169 rootElement();
170
171 m_focusEventHook = SetWinEventHook(EVENT_OBJECT_FOCUS, EVENT_OBJECT_FOCUS, GetModuleHandle(0), logEventProc, GetCurrentProcessId(), 0, WINEVENT_INCONTEXT);
172
173 ASSERT(m_focusEventHook);
174 }
175
setLogValueChangeEvents(bool logValueChangeEvents)176 void AccessibilityController::setLogValueChangeEvents(bool logValueChangeEvents)
177 {
178 if (!!m_valueChangeEventHook == logValueChangeEvents)
179 return;
180
181 if (!logValueChangeEvents) {
182 UnhookWinEvent(m_valueChangeEventHook);
183 m_valueChangeEventHook = 0;
184 return;
185 }
186
187 // Ensure that accessibility is initialized for the WebView by querying for
188 // the root accessible object.
189 rootElement();
190
191 m_valueChangeEventHook = SetWinEventHook(EVENT_OBJECT_VALUECHANGE, EVENT_OBJECT_VALUECHANGE, GetModuleHandle(0), logEventProc, GetCurrentProcessId(), 0, WINEVENT_INCONTEXT);
192
193 ASSERT(m_valueChangeEventHook);
194 }
195
setLogScrollingStartEvents(bool logScrollingStartEvents)196 void AccessibilityController::setLogScrollingStartEvents(bool logScrollingStartEvents)
197 {
198 if (!!m_scrollingStartEventHook == logScrollingStartEvents)
199 return;
200
201 if (!logScrollingStartEvents) {
202 UnhookWinEvent(m_scrollingStartEventHook);
203 m_scrollingStartEventHook = 0;
204 return;
205 }
206
207 // Ensure that accessibility is initialized for the WebView by querying for
208 // the root accessible object.
209 rootElement();
210
211 m_scrollingStartEventHook = SetWinEventHook(EVENT_SYSTEM_SCROLLINGSTART, EVENT_SYSTEM_SCROLLINGSTART, GetModuleHandle(0), logEventProc, GetCurrentProcessId(), 0, WINEVENT_INCONTEXT);
212
213 ASSERT(m_scrollingStartEventHook);
214 }
215
setLogAccessibilityEvents(bool)216 void AccessibilityController::setLogAccessibilityEvents(bool)
217 {
218 }
219
stringEvent(DWORD event)220 static string stringEvent(DWORD event)
221 {
222 switch(event) {
223 case EVENT_OBJECT_VALUECHANGE:
224 return "value change event";
225 default:
226 return "unknown event";
227 }
228 }
229
notificationListenerProc(HWINEVENTHOOK,DWORD event,HWND hwnd,LONG idObject,LONG idChild,DWORD,DWORD)230 static void CALLBACK notificationListenerProc(HWINEVENTHOOK, DWORD event, HWND hwnd, LONG idObject, LONG idChild, DWORD, DWORD)
231 {
232 // Get the accessible object for this event.
233 COMPtr<IAccessible> parentObject;
234
235 VARIANT vChild;
236 VariantInit(&vChild);
237
238 HRESULT hr = AccessibleObjectFromEvent(hwnd, idObject, idChild, &parentObject, &vChild);
239 if (FAILED(hr) || !parentObject)
240 return;
241
242 COMPtr<IDispatch> childDispatch;
243 if (FAILED(parentObject->get_accChild(vChild, &childDispatch))) {
244 VariantClear(&vChild);
245 return;
246 }
247
248 COMPtr<IAccessible> childAccessible(Query, childDispatch);
249
250 sharedFrameLoadDelegate->accessibilityController()->notificationReceived(childAccessible, stringEvent(event));
251
252 VariantClear(&vChild);
253 }
254
comparableObject(const COMPtr<IServiceProvider> & serviceProvider)255 static COMPtr<IAccessibleComparable> comparableObject(const COMPtr<IServiceProvider>& serviceProvider)
256 {
257 COMPtr<IAccessibleComparable> comparable;
258 serviceProvider->QueryService(SID_AccessibleComparable, __uuidof(IAccessibleComparable), reinterpret_cast<void**>(&comparable));
259 return comparable;
260 }
261
notificationReceived(PlatformUIElement element,const string & eventName)262 void AccessibilityController::notificationReceived(PlatformUIElement element, const string& eventName)
263 {
264 for (HashMap<PlatformUIElement, JSObjectRef>::iterator it = m_notificationListeners.begin(); it != m_notificationListeners.end(); ++it) {
265 COMPtr<IServiceProvider> thisServiceProvider(Query, it->first);
266 if (!thisServiceProvider)
267 continue;
268
269 COMPtr<IAccessibleComparable> thisComparable = comparableObject(thisServiceProvider);
270 if (!thisComparable)
271 continue;
272
273 COMPtr<IServiceProvider> elementServiceProvider(Query, element);
274 if (!elementServiceProvider)
275 continue;
276
277 COMPtr<IAccessibleComparable> elementComparable = comparableObject(elementServiceProvider);
278 if (!elementComparable)
279 continue;
280
281 BOOL isSame = FALSE;
282 thisComparable->isSameObject(elementComparable.get(), &isSame);
283 if (!isSame)
284 continue;
285
286 JSRetainPtr<JSStringRef> jsNotification(Adopt, JSStringCreateWithUTF8CString(eventName.c_str()));
287 JSValueRef argument = JSValueMakeString(frame->globalContext(), jsNotification.get());
288 JSObjectCallAsFunction(frame->globalContext(), it->second, NULL, 1, &argument, NULL);
289 }
290 }
291
addNotificationListener(PlatformUIElement element,JSObjectRef functionCallback)292 void AccessibilityController::addNotificationListener(PlatformUIElement element, JSObjectRef functionCallback)
293 {
294 if (!m_allEventsHook)
295 m_allEventsHook = SetWinEventHook(EVENT_MIN, EVENT_MAX, GetModuleHandle(0), notificationListenerProc, GetCurrentProcessId(), 0, WINEVENT_INCONTEXT);
296
297 JSValueProtect(frame->globalContext(), functionCallback);
298 m_notificationListeners.add(element, functionCallback);
299 }
300