Fix get_accFocus() to return CHILDID_SELF when it returns itself.

This means that the AT client knows it should not have to ask for
the focus child anymore.
Previously, some clients (NVDA) kept on asking infinitely because of
this.

Change-Id: Ia2bd2e1088a899f7d1a0c9189024accdacfd693b
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@nokia.com>

diff --git a/src/plugins/platforms/windows/qwindowsaccessibility.cpp b/src/plugins/platforms/windows/qwindowsaccessibility.cpp
index 4c24cdd..1a8f593 100644 (file)
--- a/src/plugins/platforms/windows/qwindowsaccessibility.cpp
+++ b/src/plugins/platforms/windows/qwindowsaccessibility.cpp
@@ -121,6 +121,21 @@ void accessibleDebugClientCalls_helper(const char* funcName, const QAccessibleIn
 
 typedef QSharedPointer<QAccessibleInterface> QAIPointer;
 
+static bool compareAccessible(QAccessibleInterface *one, QAccessibleInterface *other)
+{
+    if (one == other) return true;
+    if (!one || !other) return false;
+
+    if (one->object() && other->object() && (one->object() == other->object()))
+        return true;
+    QAIPointer onePar(one->parent());
+    QAIPointer otherPar(other->parent());
+
+    if (compareAccessible(onePar.data(), otherPar.data()))
+        return onePar->indexOfChild(one) == otherPar->indexOfChild(other);
+    return false;
+}
+
 // This stuff is used for widgets/items with no window handle:
 typedef QMap<int, QPair<QObject*,int> > NotifyMap;
 Q_GLOBAL_STATIC(NotifyMap, qAccessibleRecentSentEvents)
@@ -1221,7 +1236,22 @@ HRESULT STDMETHODCALLTYPE QWindowsAccessible::accSelect(long flagsSelect, VARIAN
     return res ? S_OK : S_FALSE;
 }
 
-// moz: [important]
+/*!
+    \internal
+    Can return:
+
+  +-------------+------------------------------------------------------------------------------+
+  | VT_EMPTY    | None. Neither this object nor any of its children has the keyboard focus.    |
+  +-------------+------------------------------------------------------------------------------+
+  | VT_I4       | lVal is CHILDID_SELF. The object itself has the keyboard focus.              |
+  +-------------+------------------------------------------------------------------------------+
+  | VT_I4       | lVal contains the child ID of the child element that has the keyboard focus. |
+  +-------------+------------------------------------------------------------------------------+
+  | VT_DISPATCH | pdispVal member is the address of the IDispatch interface for the child      |
+  |             | object that has the keyboard focus.                                          |
+  +-------------+------------------------------------------------------------------------------+
+    moz: [important]
+*/
 HRESULT STDMETHODCALLTYPE QWindowsAccessible::get_accFocus(VARIANT *pvarID)
 {
     accessibleDebugClientCalls(accessible);
@@ -1229,16 +1259,20 @@ HRESULT STDMETHODCALLTYPE QWindowsAccessible::get_accFocus(VARIANT *pvarID)
         return E_FAIL;
 
     if (QAccessibleInterface *acc = accessible->focusChild()) {
-        QWindowsAccessible* wacc = new QWindowsAccessible(acc);
-        IDispatch *iface = 0;
-        wacc->QueryInterface(IID_IDispatch, (void**)&iface);
-        if (iface) {
+        if (compareAccessible(acc, accessible)) {
+            (*pvarID).vt = VT_I4;
+            (*pvarID).lVal = CHILDID_SELF;
+            delete acc;
+            return S_OK;
+        } else {
+            QWindowsAccessible* wacc = new QWindowsAccessible(acc);
+            IDispatch *iface = 0;
+            wacc->QueryInterface(IID_IDispatch, (void**)&iface);
             (*pvarID).vt = VT_DISPATCH;
             (*pvarID).pdispVal = iface;
             return S_OK;
-        } else {
-            delete wacc;
         }
+        delete acc;
     }
     (*pvarID).vt = VT_EMPTY;
     return S_FALSE;