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, 17 insertions, 7 deletions

diff --git a/src/plugins/accessible/widgets/qaccessiblemenu.cpp b/src/plugins/accessible/widgets/qaccessiblemenu.cpp
index e467ef50bd..f248e6d05e 100644
--- a/src/plugins/accessible/widgets/qaccessiblemenu.cpp
+++ b/src/plugins/accessible/widgets/qaccessiblemenu.cpp
@@ -55,6 +55,16 @@ QT_BEGIN_NAMESPACE
 QString Q_GUI_EXPORT qt_accStripAmp(const QString &text);
 QString Q_GUI_EXPORT qt_accHotKey(const QString &text);
 
+QAccessibleInterface *getOrCreateMenu(QWidget *menu, QAction *action)
+{
+    QAccessibleInterface *iface = QAccessible::queryAccessibleInterface(action);
+    if (!iface) {
+        iface = new QAccessibleMenuItem(menu, action);
+        QAccessible::registerAccessibleInterface(iface);
+    }
+    return iface;
+}
+
 QAccessibleMenu::QAccessibleMenu(QWidget *w)
 : QAccessibleWidget(w)
 {
@@ -76,7 +86,7 @@ QAccessibleInterface *QAccessibleMenu::childAt(int x, int y) const
     QAction *act = menu()->actionAt(menu()->mapFromGlobal(QPoint(x,y)));
     if(act && act->isSeparator())
         act = 0;
-    return act ? new QAccessibleMenuItem(menu(), act) : 0;
+    return act ? getOrCreateMenu(menu(), act) : 0;
 }
 
 QString QAccessibleMenu::text(QAccessible::Text t) const
@@ -98,7 +108,7 @@ QAccessible::Role QAccessibleMenu::role() const
 QAccessibleInterface *QAccessibleMenu::child(int index) const
 {
     if (index < childCount())
-        return new QAccessibleMenuItem(menu(), menu()->actions().at(index));
+        return getOrCreateMenu(menu(), menu()->actions().at(index));
     return 0;
 }
 
@@ -111,7 +121,7 @@ QAccessibleInterface *QAccessibleMenu::parent() const
         foreach (QWidget *w, parentCandidates) {
             if (qobject_cast<QMenu*>(w) || qobject_cast<QMenuBar*>(w)) {
                 if (w->actions().indexOf(menuAction) != -1)
-                    return new QAccessibleMenuItem(w, menuAction);
+                    return getOrCreateMenu(w, menuAction);
             }
         }
     }
@@ -146,8 +156,9 @@ int QAccessibleMenuBar::childCount() const
 
 QAccessibleInterface *QAccessibleMenuBar::child(int index) const
 {
-    if (index < childCount())
-        return new QAccessibleMenuItem(menuBar(), menuBar()->actions().at(index));
+    if (index < childCount()) {
+        return getOrCreateMenu(menuBar(), menuBar()->actions().at(index));
+    }
     return 0;
 }
 
@@ -177,7 +188,6 @@ QAccessibleInterface *QAccessibleMenuItem::childAt(int x, int y ) const
         if (childInterface->rect().contains(x,y)) {
             return childInterface;
         }
-        delete childInterface;
     }
     return 0;
 }
@@ -207,7 +217,7 @@ QAccessibleInterface *QAccessibleMenuItem::parent() const
 QAccessibleInterface *QAccessibleMenuItem::child(int index) const
 {
     if (index == 0 && action()->menu())
-        return new QAccessibleMenu(action()->menu());
+        return QAccessible::queryAccessibleInterface(action()->menu());
     return 0;
 }