Cache QAccessibleInterfaces.

Since there already is a one-to-one relationship
between QObject and QAccessibleInterface it makes
little sense to create and destroy the interfaces
on each call to queryAccessibleInterface.

Add a cache and keep created interfaces around for
the lifetime of the corresponding QObject.

This changes the memory management rules: accessible
interfaces must no longer be deleted. If you get an
QAccessibleIntrface pointer that pointer will stay
valid as long as the corresponding QObject is not
deleted.

This also re-enables accessibility for Mac.

We limit the range of the IDs so that they are
useable for Windows directly.
That means we can get rid of the event cache there.

This is based on: Iebf2f374916fc70a9dd29e95f45a6444b85f6cee

Change-Id: I9fe6531812c0dbc5b41101ac05830a6dd75e13a3
Reviewed-by: Morten Johan Sørvig <morten.sorvig@digia.com>

1 files changed, 138 insertions, 90 deletions

diff --git a/src/plugins/platforms/windows/accessible/iaccessible2.cpp b/src/plugins/platforms/windows/accessible/iaccessible2.cpp
index 44e715d0ce..b1afd7aca3 100644
--- a/src/plugins/platforms/windows/accessible/iaccessible2.cpp
+++ b/src/plugins/platforms/windows/accessible/iaccessible2.cpp
@@ -230,6 +230,10 @@ HRESULT STDMETHODCALLTYPE AccessibleRelation::get_targets(
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::QueryInterface(REFIID id, LPVOID *iface)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
+    if (!accessible)
+        return E_NOINTERFACE;
+
     HRESULT hr = QWindowsMsaaAccessible::QueryInterface(id, iface);
     if (!SUCCEEDED(hr)) {
         if (id == IID_IServiceProvider) {
@@ -301,10 +305,11 @@ ULONG STDMETHODCALLTYPE QWindowsIA2Accessible::Release()
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nRelations(long *nRelations)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (!nRelations)
       return E_INVALIDARG;
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     return getRelationsHelper(0, 0, 0, nRelations);
@@ -312,10 +317,11 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nRelations(long *nRelations
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_relation(long relationIndex, IAccessibleRelation **relation)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (!relation)
       return E_INVALIDARG;
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     return getRelationsHelper(relation, relationIndex,  1);
@@ -330,8 +336,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_relations(long maxRelations
                                         IAccessibleRelation **relations,
                                         long *nRelations)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     return getRelationsHelper(relations, 0, maxRelations, nRelations);
@@ -340,8 +347,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_relations(long maxRelations
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::role(long *ia2role)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     long r = accessible->role();
@@ -386,8 +394,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_groupPosition(long *groupLe
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_states(AccessibleStates *states)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (!states)
         return E_POINTER;
@@ -462,23 +471,23 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_localizedExtendedStates(lon
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_uniqueID(long *outUniqueID)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
-    // ### FIXME SERIOUSLY, NOT A STABLE SOLUTION IF NODES ARE DELETED ETC
-    // Return 0 if no object and no parent. This is really an error case.
-    uint uid = uniqueID();
-    accessibleDebug("uniqueID: %08x", uid);
 
-    *outUniqueID = (long)uid;
-    return uid ? S_OK : S_FALSE;
+    accessibleDebug("uniqueID: %08x", id);
+
+    *outUniqueID = (long)id;
+    return int(id) < 0 ? S_OK : S_FALSE;
 }
 
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_windowHandle(HWND *windowHandle)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     return GetWindow(windowHandle);
 }
@@ -486,8 +495,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_windowHandle(HWND *windowHa
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_indexInParent(long *indexInParent)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (!indexInParent)
       return E_INVALIDARG;
@@ -497,7 +507,6 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_indexInParent(long *indexIn
         return S_FALSE;
     }
     int indexOfChild = par->indexOfChild(accessible);
-    delete par;
     Q_ASSERT(indexOfChild >= 0);
     *indexInParent = indexOfChild;
     return S_OK;
@@ -505,8 +514,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_indexInParent(long *indexIn
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_locale(IA2Locale *locale)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     IA2Locale res;
     QLocale l;
@@ -519,8 +529,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_locale(IA2Locale *locale)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_attributes(BSTR *attributes)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *attributes = 0;//QStringToBSTR(QString());
     return S_FALSE;
@@ -531,8 +542,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_attributes(BSTR *attributes
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::nActions(long *nActions)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *nActions = 0;
 
@@ -543,8 +555,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::nActions(long *nActions)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::doAction(long actionIndex)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (QAccessibleActionInterface *actionIface = actionInterface()) {
         const QStringList actionNames = actionIface->actionNames();
@@ -559,8 +572,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::doAction(long actionIndex)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_description(long actionIndex, BSTR *description)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *description = 0;
     if (QAccessibleActionInterface *actionIface = actionInterface()) {
@@ -575,8 +589,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_description(long actionInde
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_keyBinding(long actionIndex, long nMaxBindings, BSTR **keyBindings, long *nBindings)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     Q_UNUSED(nMaxBindings);
     BSTR *arrayOfBindingsToReturn = 0;
@@ -603,8 +618,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_keyBinding(long actionIndex
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_name(long actionIndex, BSTR *name)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *name = 0;
     if (QAccessibleActionInterface *actionIface = actionInterface()) {
@@ -619,8 +635,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_name(long actionIndex, BSTR
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_localizedName(long actionIndex, BSTR *localizedName)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *localizedName = 0;
     if (QAccessibleActionInterface *actionIface = actionInterface()) {
@@ -639,8 +656,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_localizedName(long actionIn
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_locationInParent(long *x, long *y)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     QPoint topLeft = accessible->rect().topLeft();
@@ -656,8 +674,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_locationInParent(long *x, l
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_foreground(IA2Color *foreground)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     // IA2Color is a typedef for long
@@ -667,8 +686,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_foreground(IA2Color *foregr
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_background(IA2Color *background)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     // IA2Color is a typedef for long
@@ -687,6 +707,8 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_background(IA2Color *backgr
 */
 QString QWindowsIA2Accessible::textForRange(int startOffset, int endOffset) const
 {
+    QAccessibleInterface *accessible = accessibleInterface();
+
     if (QAccessibleTextInterface *textIface = accessible->textInterface()) {
         if (endOffset == IA2_TEXT_OFFSET_LENGTH)
             endOffset = textIface->characterCount();
@@ -704,6 +726,7 @@ QString QWindowsIA2Accessible::textForRange(int startOffset, int endOffset) cons
 */
 void QWindowsIA2Accessible::replaceTextFallback(long startOffset, long endOffset, const QString &txt)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     QString t = textForRange(0, -1);
     if (endOffset == IA2_TEXT_OFFSET_LENGTH)
         endOffset = t.length();
@@ -717,6 +740,7 @@ void QWindowsIA2Accessible::replaceTextFallback(long startOffset, long endOffset
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::copyText(long startOffset, long endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
 #ifndef QT_NO_CLIPBOARD
     const QString t = textForRange(startOffset, endOffset);
@@ -729,6 +753,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::copyText(long startOffset, long
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::deleteText(long startOffset, long endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleEditableTextInterface *editableTextIface = accessible->editableTextInterface())
         editableTextIface->deleteText(startOffset, endOffset);
@@ -739,6 +764,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::deleteText(long startOffset, lo
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::insertText(long offset, BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     const QString txt(BSTRToQString(*text));
     if (QAccessibleEditableTextInterface *editableTextIface = accessible->editableTextInterface())
@@ -750,6 +776,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::insertText(long offset, BSTR *t
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::cutText(long startOffset, long endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
 #ifndef QT_NO_CLIPBOARD
     const QString t = textForRange(startOffset, endOffset);
@@ -766,6 +793,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::cutText(long startOffset, long
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::pasteText(long offset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
 #ifndef QT_NO_CLIPBOARD
     const QString txt = QGuiApplication::clipboard()->text();
@@ -781,6 +809,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::pasteText(long offset)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::replaceText(long startOffset, long endOffset, BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     const QString txt(BSTRToQString(*text));
     if (QAccessibleEditableTextInterface *editableTextIface = accessible->editableTextInterface())
@@ -801,8 +830,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setAttributes(long /*startOffse
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_cellAt( long row, long column, IUnknown **cell)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *cell = 0;
@@ -817,8 +847,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_cellAt( long row, long colu
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_caption( IUnknown **captionInterface)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *captionInterface = 0;
@@ -831,8 +862,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_caption( IUnknown **caption
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnDescription( long column, BSTR *description)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *description = 0;
@@ -846,8 +878,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnDescription( long col
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nColumns( long *columnCount)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -859,8 +892,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nColumns( long *columnCount
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nRows(long *rowCount)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -872,8 +906,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nRows(long *rowCount)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedCells(long *cellCount)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -885,8 +920,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedCells(long *cellCo
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedColumns(long *columnCount)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -898,8 +934,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedColumns(long *colu
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedRows(long *rowCount)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -911,8 +948,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelectedRows(long *rowCoun
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowDescription(long row, BSTR *description)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *description = 0;
@@ -926,10 +964,11 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowDescription(long row, BS
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedCells(IUnknown ***cells, long *nSelectedCells)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     Q_UNUSED(cells);
     Q_UNUSED(nSelectedCells);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     QList<QAccessibleInterface*> selectedCells = tableInterface()->selectedCells();
@@ -938,8 +977,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedCells(IUnknown ***c
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedColumns(long **selectedColumns, long *nColumns)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -958,8 +998,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedColumns(long **sele
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedRows(long **selectedRows, long *nRows)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -978,8 +1019,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selectedRows(long **selecte
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_summary(IUnknown **summaryInterface)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *summaryInterface = 0;
@@ -992,8 +1034,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_summary(IUnknown **summaryI
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_isColumnSelected(long column, boolean *isSelected)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1005,8 +1048,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_isColumnSelected(long colum
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_isRowSelected(long row, boolean *isSelected)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1018,8 +1062,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_isRowSelected(long row, boo
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::selectRow(long row)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1031,8 +1076,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::selectRow(long row)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::selectColumn(long column)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1044,8 +1090,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::selectColumn(long column)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::unselectRow(long row)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1057,8 +1104,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::unselectRow(long row)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::unselectColumn(long column)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     if (QAccessibleTableInterface *tableIface = tableInterface()) {
@@ -1070,8 +1118,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::unselectColumn(long column)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_modelChange( IA2TableModelChange * /*modelChange*/)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     return E_NOTIMPL;
 }
@@ -1081,8 +1130,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_modelChange( IA2TableModelC
 \**************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnExtent(long *nColumnsSpanned)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     *nColumnsSpanned = tableCellInterface()->columnExtent();
@@ -1092,8 +1142,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnExtent(long *nColumns
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnHeaderCells(IUnknown ***cellAccessibles,
                                                                     long *nColumnHeaderCells)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     const QList<QAccessibleInterface*> headerCells = tableCellInterface()->columnHeaderCells();
     return wrapListOfCells(headerCells, cellAccessibles, nColumnHeaderCells);
@@ -1101,8 +1152,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnHeaderCells(IUnknown
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnIndex(long *columnIndex)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *columnIndex = tableCellInterface()->columnIndex();
     return S_OK;
@@ -1110,8 +1162,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_columnIndex(long *columnInd
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowExtent(long *nRowsSpanned)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *nRowsSpanned = tableCellInterface()->rowExtent();
     return S_OK;
@@ -1120,8 +1173,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowExtent(long *nRowsSpanne
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowHeaderCells(IUnknown ***cellAccessibles,
                                                                  long *nRowHeaderCells)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     const QList<QAccessibleInterface*> headerCells = tableCellInterface()->rowHeaderCells();
     return wrapListOfCells(headerCells, cellAccessibles, nRowHeaderCells);
@@ -1129,8 +1183,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowHeaderCells(IUnknown ***
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowIndex(long *rowIndex)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *rowIndex = tableCellInterface()->rowIndex();
     return S_OK;
@@ -1138,8 +1193,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowIndex(long *rowIndex)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_isSelected( boolean *isSelected)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     *isSelected = tableCellInterface()->isSelected();
     return S_OK;
@@ -1149,8 +1205,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowColumnExtents(long *row,
                                                long *rowExtents, long *columnExtents,
                                                boolean *isSelected)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     tableCellInterface()->rowColumnExtents((int*)row, (int*)column, (int*)rowExtents, (int*)columnExtents, (bool*)isSelected);
@@ -1159,8 +1216,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_rowColumnExtents(long *row,
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_table(IUnknown **table)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
 
     QAccessibleInterface *tableIface = tableCellInterface()->table();
@@ -1175,6 +1233,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_table(IUnknown **table)
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::addSelection(long startOffset,
                                                            long endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         text->addSelection(startOffset, endOffset);
@@ -1188,6 +1247,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_attributes(long offset,
                                                              long *endOffset,
                                                              BSTR *textAttributes)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         const QString attrs = text->attributes(offset, (int*)startOffset, (int*)endOffset);
@@ -1199,6 +1259,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_attributes(long offset,
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_caretOffset(long *offset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         *offset = text->cursorPosition();
@@ -1215,6 +1276,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_characterExtents(long offse
                                                                    long *width,
                                                                    long *height)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         QRect rect = text->characterRect(offset);
@@ -1228,6 +1290,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_characterExtents(long offse
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nSelections(long *nSelections)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         *nSelections = text->selectionCount();
@@ -1241,6 +1304,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_offsetAtPoint(long x,
                                                                 enum IA2CoordinateType coordType,
                                                                 long *offset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         QPoint screenPos = mapToScreenPos(coordType, x, y);
@@ -1255,6 +1319,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_selection(long selectionInd
                                                             long *startOffset,
                                                             long *endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *text = textInterface()) {
         text->selection(selectionIndex, (int*)startOffset, (int*)endOffset);
@@ -1267,6 +1332,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_text(long startOffset,
                                                        long endOffset,
                                                        BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textif = textInterface()) {
         const QString t = textif->text(startOffset, endOffset);
@@ -1285,6 +1351,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_textBeforeOffset(long offse
                                                long *endOffset,
                                                BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         const QString txt = textIface->textBeforeOffset(offset, (QAccessible2::BoundaryType)boundaryType, (int*)startOffset, (int*)endOffset);
@@ -1304,6 +1371,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_textAfterOffset(
     long *endOffset,
     BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         const QString txt = textIface->textAfterOffset(offset, (QAccessible2::BoundaryType)boundaryType, (int*)startOffset, (int*)endOffset);
@@ -1322,6 +1390,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_textAtOffset(long offset,
                                                                long *endOffset,
                                                                BSTR *text)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         const QString txt = textIface->textAtOffset(offset, (QAccessible2::BoundaryType)boundaryType, (int*)startOffset, (int*)endOffset);
@@ -1336,6 +1405,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_textAtOffset(long offset,
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::removeSelection(long selectionIndex)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         textIface->removeSelection(selectionIndex);
@@ -1346,6 +1416,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::removeSelection(long selectionI
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setCaretOffset(long offset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         textIface->setCursorPosition(offset);
@@ -1358,6 +1429,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setSelection(long selectionInde
                                                            long startOffset,
                                                            long endOffset)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         textIface->setSelection(selectionIndex, startOffset, endOffset);
@@ -1368,6 +1440,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setSelection(long selectionInde
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_nCharacters(long *nCharacters)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         *nCharacters = textIface->characterCount();
@@ -1380,6 +1453,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::scrollSubstringTo(long startInd
                                                                 long endIndex,
                                                                 enum IA2ScrollType scrollType)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
     if (QAccessibleTextInterface *textIface = textInterface()) {
         Q_UNUSED(scrollType);   //###
@@ -1421,8 +1495,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_oldText(IA2TextSegment *old
  **************************************************************/
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_currentValue(VARIANT *currentValue)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (QAccessibleValueInterface *valueIface = valueInterface()) {
         const QVariant var = valueIface->currentValue();
@@ -1436,8 +1511,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_currentValue(VARIANT *curre
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setCurrentValue(VARIANT value)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     HRESULT hr = S_FALSE;
     if (QAccessibleValueInterface *valueIface = valueInterface()) {
@@ -1452,8 +1528,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::setCurrentValue(VARIANT value)
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_maximumValue(VARIANT *maximumValue)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (QAccessibleValueInterface *valueIface = valueInterface()) {
         const QVariant var = valueIface->maximumValue();
@@ -1466,8 +1543,9 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_maximumValue(VARIANT *maxim
 
 HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::get_minimumValue(VARIANT *minimumValue)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     accessibleDebugClientCalls(accessible);
-    if (!accessible->isValid())
+    if (!accessible)
         return E_FAIL;
     if (QAccessibleValueInterface *valueIface = valueInterface()) {
         const QVariant var = valueIface->minimumValue();
@@ -1539,6 +1617,7 @@ HRESULT STDMETHODCALLTYPE QWindowsIA2Accessible::QueryService(REFGUID guidServic
 */
 HRESULT QWindowsIA2Accessible::getRelationsHelper(IAccessibleRelation **relations, int startIndex, long maxRelations, long *nRelations /* = 0*/)
 {
+    QAccessibleInterface *accessible = accessibleInterface();
     if (nRelations)
         *nRelations = 0;
     typedef QPair<QAccessibleInterface *, QAccessible::Relation> RelationEntry;
@@ -1588,37 +1667,6 @@ HRESULT QWindowsIA2Accessible::wrapListOfCells(const QList<QAccessibleInterface*
     return count > 0 ? S_OK : S_FALSE;
 }
 
-uint QWindowsIA2Accessible::uniqueID() const
-{
-    uint uid = 0;
-    if (QObject *obj = accessible->object())
-        uid = qHash(obj);
-
-    if (!uid) {
-        QAccessibleInterface *acc = accessible;
-        QVector<int> indexOfNodes;
-        while (acc && acc->isValid() && !acc->object()) {
-            QAccessibleInterface *par = acc->parent();
-            indexOfNodes.append(par->indexOfChild(acc));
-            if (acc != accessible)
-                delete acc;
-            acc = par;
-        }
-        if (acc) {
-            if (acc->object()) {
-                uid = qHash(acc->object());
-                for (int i = 0; i < indexOfNodes.count(); ++i)
-                    uid = qHash(uid + indexOfNodes.at(i));
-
-            }
-            if (acc != accessible)
-                delete acc;
-        }
-    }
-    return uid;
-}
-
-
 #define IF_EQUAL_RETURN_IIDSTRING(id, iid) if (id == iid) return QByteArray(#iid)
 
 QByteArray QWindowsIA2Accessible::IIDToString(REFIID id)