qt a11y: Remember associated QObject also for non-QtXAcccessible case

This is similar to what
Change-Id Ic890a387ff016e889f25dba70c82d0d81ae7a9e3
("qt a11y: Remember and reuse existing QObject for XAccessible")
does to avoid creating another `QtXAccessible` for an `XAccessible`
if one has been created earlier.

However, there is an additional case that needs to be
covered to avoid creating multiple `QObjects` for
a single `XAccessible`:

`QtAccessibleWidget::customFactory` not only gets called
by explicitly calling `QAccessible::queryAccessibleInterface`
from within LibreOffice code, but the Qt library itself
also calls this method, in which case no entry associating
the `XAccessible` with its `QObject` had been inserted into
the map handled by our `QtAccessibleRegistry` previously.

This would result in a "new" `QtXAccessible` object
being created later when a `QObject` would be needed
for that `XAccessible`, rather than using the
`QtWidget` that is the actual `QObject` associated
with the object.

Prevent that from happening by inserting an entry
into the map for this case as well.

With this and two Accerciser fixes [1] [2] in place, jumping
to bookmarks in Accerciser's treeview of the LO a11y
hierarchy now generally works with the qt6 VCL plugin.

It previously failed due to the fact that a new object
was created and navigating the tree up to the root application
object from the bookmarked object would then fail.

The fact that there were two objects could be seen e.g. by
using the following commands in Accerciser's IPython console
with the root "soffice.bin" application a11y object
selected in the treeview after starting Calc:

In [25]: acc[1][0][0].get_parent().path
Out[25]: '/org/a11y/atspi/accessible/2147483672'
In [26]: acc[1][0].path
Out[26]: '/org/a11y/atspi/accessible/2147483648'

-> Two different IDs/paths for what should be the same object.
(The parent of the first child of the object at tree path 1,0
should be the object itself, but here it wasn't.)

With this change in place, this now works as expected:

In [28]: acc[1][0][0].get_parent().path
Out[28]: '/org/a11y/atspi/accessible/2147483648'
In [29]: acc[1][0].path
Out[29]: '/org/a11y/atspi/accessible/2147483648'

Together with
Change-Id Ic890a387ff016e889f25dba70c82d0d81ae7a9e3
("qt a11y: Remember and reuse existing QObject for XAccessible"),
this also addresses the remaining issue mentioned in

commit 99640693d28ca11b31a1d3855e104d2d8c5122d7
Author: Michael Weghorn <m.weghorn@posteo.de>
Date:   Wed Aug 3 16:49:48 2022 +0200

> Note however that this change alone is not yet sufficient
> for a window to actually be returned for any arbitrary a11y
> object deeper down the hierarchy. This is because
> walking up the a11y hierarchy currently results in new
> Qt a11y objects being created for the parents instead of
> using existing ones, and the newly created ones lack
> the association to the widgets.
> (This works in a WIP branch that remembers/caches
> a11y objects, but that needs some additional work before
> it can be merged.)

Note that there are still cases where navigation
to bookmarks in Accerciser's tree view doesn't work
(reliably), but those would need to be looked at
separately and might not be specific to the qt6
VCL plugin. (At least I have come across such
cases with gtk3 as well.)

[1] https://gitlab.gnome.org/GNOME/accerciser/-/commit/c2a3e9f1eb1fcd6eb059f1f2fe6e629b86521335
[2] https://gitlab.gnome.org/GNOME/accerciser/-/commit/a092dc933985fafd5b1e2cc3374c7bbc0fb2d12e

Change-Id: I02262014a45a4b024cdc1bbd385da8a35a2c304a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/138764
Tested-by: Jenkins
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>

2 files changed, 15 insertions, 1 deletions

diff --git a/vcl/qt5/QtAccessibleRegistry.cxx b/vcl/qt5/QtAccessibleRegistry.cxx
index e64f8ae03868..88f9abcfd17e 100644
--- a/vcl/qt5/QtAccessibleRegistry.cxx
+++ b/vcl/qt5/QtAccessibleRegistry.cxx
@@ -10,6 +10,8 @@
 #include <QtAccessibleRegistry.hxx>
 #include <QtXAccessible.hxx>
 
+#include <cassert>
+
 std::map<XAccessible*, QObject*> QtAccessibleRegistry::m_aMapping = {};
 
 QObject* QtAccessibleRegistry::getQObject(css::uno::Reference<XAccessible> xAcc)
@@ -28,6 +30,12 @@ QObject* QtAccessibleRegistry::getQObject(css::uno::Reference<XAccessible> xAcc)
     return pQtAcc;
 }
 
+void QtAccessibleRegistry::insert(css::uno::Reference<XAccessible> xAcc, QObject* pQObject)
+{
+    assert(pQObject);
+    m_aMapping.emplace(xAcc.get(), pQObject);
+}
+
 void QtAccessibleRegistry::remove(css::uno::Reference<XAccessible> xAcc)
 {
     assert(xAcc.is());
diff --git a/vcl/qt5/QtAccessibleWidget.cxx b/vcl/qt5/QtAccessibleWidget.cxx
index fc81332465e7..e2e99e6de208 100644
--- a/vcl/qt5/QtAccessibleWidget.cxx
+++ b/vcl/qt5/QtAccessibleWidget.cxx
@@ -755,7 +755,13 @@ QAccessibleInterface* QtAccessibleWidget::customFactory(const QString& classname
         vcl::Window* pWindow = pWidget->frame().GetWindow();
 
         if (pWindow)
-            return new QtAccessibleWidget(pWindow->GetAccessible(), object);
+        {
+            css::uno::Reference<XAccessible> xAcc = pWindow->GetAccessible();
+            // insert into registry so the association between the XAccessible and the QtWidget
+            // is remembered rather than creating a different QtXAccessible when a QObject is needed later
+            QtAccessibleRegistry::insert(xAcc, object);
+            return new QtAccessibleWidget(xAcc, object);
+        }
     }
     if (classname == QLatin1String("QtXAccessible") && object)
     {