From 3f7ac5540c8796ec2bb2b595ca6648035a0f8b18 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Morten=20Johan=20S=C3=B8rvig?= <morten.sorvig@qt.io>
Date: Fri, 7 May 2021 10:07:50 +0200
Subject: [PATCH 09/19] Implement accessibility for QQuickWidget
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The accessibility tree for the Qt Quick content should
be rooted at the QQuickWidget, and not at the offscreen
QQuickWindow.

For this to be the case, several things must happen:
  - QQuickWindow must not report the child interfaces
  - QQuickWidget must report the child interfaces
  - The child interfaces must report the QQuickWidget as the parent

Create accessibility interfaces for QQuickWidget and
and QQuickWigetOffscreenWindow (which now gets a proper
subclass), where the QQuickWidget interface reports
the child interfaces and the QQuickWigetOffscreenWindow
reports no children

Change the code in QAccessibleQuickItem to use the
true (visible) window, where needed.

Fixes: QTBUG-67290
Change-Id: I387d0ef711138d248a8dd16eefc9839499b35eeb
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
(cherry picked from commit 41926e08d73ea6c4bbfc87a1dd52d2cdbc435c27)
---
 src/quick/accessible/qaccessiblequickitem.cpp |  29 +++--
 src/quick/accessible/qaccessiblequickview_p.h |   2 +-
 src/quickwidgets/qaccessiblequickwidget.cpp   | 110 ++++++++++++++++++
 src/quickwidgets/qaccessiblequickwidget.h     |  84 +++++++++++++
 .../qaccessiblequickwidgetfactory.cpp         |  60 ++++++++++
 .../qaccessiblequickwidgetfactory_p.h         |  66 +++++++++++
 src/quickwidgets/qquickwidget.cpp             |  18 ++-
 src/quickwidgets/qquickwidget_p.h             |   8 ++
 src/quickwidgets/quickwidgets.pro             |   8 +-
 9 files changed, 368 insertions(+), 17 deletions(-)
 create mode 100644 src/quickwidgets/qaccessiblequickwidget.cpp
 create mode 100644 src/quickwidgets/qaccessiblequickwidget.h
 create mode 100644 src/quickwidgets/qaccessiblequickwidgetfactory.cpp
 create mode 100644 src/quickwidgets/qaccessiblequickwidgetfactory_p.h

diff --git a/src/quick/accessible/qaccessiblequickitem.cpp b/src/quick/accessible/qaccessiblequickitem.cpp
index ae1954ae8d..0692ce634d 100644
--- a/src/quick/accessible/qaccessiblequickitem.cpp
+++ b/src/quick/accessible/qaccessiblequickitem.cpp
@@ -46,6 +46,7 @@
 #include "QtQuick/private/qquicktextinput_p.h"
 #include "QtQuick/private/qquickaccessibleattached_p.h"
 #include "QtQuick/qquicktextdocument.h"
+#include "QtQuick/qquickrendercontrol.h"
 QT_BEGIN_NAMESPACE
 
 #if QT_CONFIG(accessibility)
@@ -57,7 +58,19 @@ QAccessibleQuickItem::QAccessibleQuickItem(QQuickItem *item)
 
 QWindow *QAccessibleQuickItem::window() const
 {
-    return item()->window();
+    QQuickWindow *window = item()->window();
+
+    // For QQuickWidget the above window will be the offscreen QQuickWindow,
+    // which is not a part of the accessibility tree. Detect this case and
+    // return the window for the QQuickWidget instead.
+    if (window && !window->handle()) {
+        if (QQuickRenderControl *renderControl = QQuickWindowPrivate::get(window)->renderControl) {
+            if (QWindow *renderWindow = renderControl->renderWindow(nullptr))
+                return renderWindow;
+        }
+    }
+
+    return window;
 }
 
 int QAccessibleQuickItem::childCount() const
@@ -113,19 +126,15 @@ QAccessibleInterface *QAccessibleQuickItem::childAt(int x, int y) const
 QAccessibleInterface *QAccessibleQuickItem::parent() const
 {
     QQuickItem *parent = item()->parentItem();
-    QQuickWindow *window = item()->window();
-    QQuickItem *ci = window ? window->contentItem() : nullptr;
+    QQuickWindow *itemWindow = item()->window();
+    QQuickItem *ci = itemWindow ? itemWindow->contentItem() : nullptr;
     while (parent && !QQuickItemPrivate::get(parent)->isAccessible && parent != ci)
         parent = parent->parentItem();
 
     if (parent) {
         if (parent == ci) {
-            // Jump out to the scene widget if the parent is the root item.
-            // There are two root items, QQuickWindow::rootItem and
-            // QQuickView::declarativeRoot. The former is the true root item,
-            // but is not a part of the accessibility tree. Check if we hit
-            // it here and return an interface for the scene instead.
-            return QAccessible::queryAccessibleInterface(window);
+            // Jump out to the window if the parent is the root item
+            return QAccessible::queryAccessibleInterface(window());
         } else {
             while (parent && !parent->d_func()->isAccessible)
                 parent = parent->parentItem();
@@ -193,7 +202,7 @@ QAccessible::State QAccessibleQuickItem::state() const
     QRect viewRect_ = viewRect();
     QRect itemRect = rect();
 
-    if (viewRect_.isNull() || itemRect.isNull() || !item()->window() || !item()->window()->isVisible() ||!item()->isVisible() || qFuzzyIsNull(item()->opacity()))
+    if (viewRect_.isNull() || itemRect.isNull() || !window() || !window()->isVisible() ||!item()->isVisible() || qFuzzyIsNull(item()->opacity()))
         state.invisible = true;
     if (!viewRect_.intersects(itemRect))
         state.offscreen = true;
diff --git a/src/quick/accessible/qaccessiblequickview_p.h b/src/quick/accessible/qaccessiblequickview_p.h
index 39ffcaf39c..8baa01330c 100644
--- a/src/quick/accessible/qaccessiblequickview_p.h
+++ b/src/quick/accessible/qaccessiblequickview_p.h
@@ -58,7 +58,7 @@ QT_BEGIN_NAMESPACE
 
 #if QT_CONFIG(accessibility)
 
-class QAccessibleQuickWindow : public QAccessibleObject
+class Q_QUICK_EXPORT QAccessibleQuickWindow : public QAccessibleObject
 {
 public:
     QAccessibleQuickWindow(QQuickWindow *object);
diff --git a/src/quickwidgets/qaccessiblequickwidget.cpp b/src/quickwidgets/qaccessiblequickwidget.cpp
new file mode 100644
index 0000000000..6f04d6693f
--- /dev/null
+++ b/src/quickwidgets/qaccessiblequickwidget.cpp
@@ -0,0 +1,110 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qaccessiblequickwidget.h"
+
+#include "qquickwidget_p.h"
+
+QT_BEGIN_NAMESPACE
+
+#if QT_CONFIG(accessibility)
+
+QAccessibleQuickWidget::QAccessibleQuickWidget(QQuickWidget* widget)
+: QAccessibleWidget(widget)
+, m_accessibleWindow(QQuickWidgetPrivate::get(widget)->offscreenWindow)
+{
+    // NOTE: m_accessibleWindow is a QAccessibleQuickWindow, and not a
+    // QAccessibleQuickWidgetOffscreenWindow (defined below). This means
+    // it will return the Quick item child interfaces, which is what's needed here
+    // (unlike QAccessibleQuickWidgetOffscreenWindow, which will report 0 children).
+}
+
+QAccessibleInterface *QAccessibleQuickWidget::child(int index) const
+{
+    return m_accessibleWindow.child(index);
+}
+
+int QAccessibleQuickWidget::childCount() const
+{
+    return m_accessibleWindow.childCount();
+}
+
+int QAccessibleQuickWidget::indexOfChild(const QAccessibleInterface *iface) const
+{
+    return m_accessibleWindow.indexOfChild(iface);
+}
+
+QAccessibleInterface *QAccessibleQuickWidget::childAt(int x, int y) const
+{
+    return m_accessibleWindow.childAt(x, y);
+}
+
+QAccessibleQuickWidgetOffscreenWindow::QAccessibleQuickWidgetOffscreenWindow(QQuickWindow *window)
+:QAccessibleQuickWindow(window)
+{
+
+}
+
+QAccessibleInterface *QAccessibleQuickWidgetOffscreenWindow::child(int index) const
+{
+    Q_UNUSED(index);
+    return nullptr;
+}
+
+int QAccessibleQuickWidgetOffscreenWindow::childCount() const
+{
+    return 0;
+}
+
+int QAccessibleQuickWidgetOffscreenWindow::indexOfChild(const QAccessibleInterface *iface) const
+{
+    Q_UNUSED(iface);
+    return -1;
+}
+
+QAccessibleInterface *QAccessibleQuickWidgetOffscreenWindow::QAccessibleQuickWidgetOffscreenWindow::childAt(int x, int y) const
+{
+    Q_UNUSED(x);
+    Q_UNUSED(y);
+    return nullptr;
+}
+
+#endif // accessibility
+
+QT_END_NAMESPACE
diff --git a/src/quickwidgets/qaccessiblequickwidget.h b/src/quickwidgets/qaccessiblequickwidget.h
new file mode 100644
index 0000000000..1f52c78c46
--- /dev/null
+++ b/src/quickwidgets/qaccessiblequickwidget.h
@@ -0,0 +1,84 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QACCESSIBLEQUICKWIDGET_H
+#define QACCESSIBLEQUICKWIDGET_H
+
+#include "qquickwidget.h"
+#include <QtWidgets/qaccessiblewidget.h>
+
+#include <private/qaccessiblequickview_p.h>
+
+QT_BEGIN_NAMESPACE
+
+#if QT_CONFIG(accessibility)
+
+// These classes implement the QQuickWiget accessibility switcharoo,
+// where the child items of the QQuickWidgetOffscreenWindow are reported
+// as child accessible interfaces of the QAccessibleQuickWidget.
+class QAccessibleQuickWidget: public QAccessibleWidget
+{
+public:
+    QAccessibleQuickWidget(QQuickWidget* widget);
+
+    QAccessibleInterface *child(int index) const override;
+    int childCount() const override;
+    int indexOfChild(const QAccessibleInterface *iface) const override;
+    QAccessibleInterface *childAt(int x, int y) const override;
+
+private:
+    QAccessibleQuickWindow m_accessibleWindow;
+    Q_DISABLE_COPY(QAccessibleQuickWidget)
+};
+
+class QAccessibleQuickWidgetOffscreenWindow: public QAccessibleQuickWindow
+{
+public:
+    QAccessibleQuickWidgetOffscreenWindow(QQuickWindow *window);
+    QAccessibleInterface *child(int index) const override;
+    int childCount() const override;
+    int indexOfChild(const QAccessibleInterface *iface) const override;
+    QAccessibleInterface *childAt(int x, int y) const override;
+};
+
+#endif // accessibility
+
+QT_END_NAMESPACE
+
+#endif
diff --git a/src/quickwidgets/qaccessiblequickwidgetfactory.cpp b/src/quickwidgets/qaccessiblequickwidgetfactory.cpp
new file mode 100644
index 0000000000..3756d0c27c
--- /dev/null
+++ b/src/quickwidgets/qaccessiblequickwidgetfactory.cpp
@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qaccessiblequickwidgetfactory_p.h"
+#include "qaccessiblequickwidget.h"
+
+QT_BEGIN_NAMESPACE
+
+#if QT_CONFIG(accessibility)
+
+QAccessibleInterface *qAccessibleQuickWidgetFactory(const QString &classname, QObject *object)
+{
+    if (classname == QLatin1String("QQuickWidget")) {
+        return new QAccessibleQuickWidget(qobject_cast<QQuickWidget *>(object));
+    } else if (classname == QLatin1String("QQuickWidgetOffscreenWindow")) {
+        return new QAccessibleQuickWidgetOffscreenWindow(qobject_cast<QQuickWindow *>(object));
+    }
+    return 0;
+}
+
+#endif // accessibility
+
+QT_END_NAMESPACE
+
diff --git a/src/quickwidgets/qaccessiblequickwidgetfactory_p.h b/src/quickwidgets/qaccessiblequickwidgetfactory_p.h
new file mode 100644
index 0000000000..8c63b09f81
--- /dev/null
+++ b/src/quickwidgets/qaccessiblequickwidgetfactory_p.h
@@ -0,0 +1,66 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtQuick module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui/qaccessible.h>
+
+#ifndef QACCESSIBLEQUICKWIDGETFACTORY_H
+#define QACCESSIBLEQUICKWIDGETFACTORY_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+#if QT_CONFIG(accessibility)
+
+QAccessibleInterface *qAccessibleQuickWidgetFactory(const QString &classname, QObject *object);
+
+#endif
+
+QT_END_NAMESPACE
+
+#endif
diff --git a/src/quickwidgets/qquickwidget.cpp b/src/quickwidgets/qquickwidget.cpp
index 223d91f579..9c97b43518 100644
--- a/src/quickwidgets/qquickwidget.cpp
+++ b/src/quickwidgets/qquickwidget.cpp
@@ -39,6 +39,7 @@
 
 #include "qquickwidget.h"
 #include "qquickwidget_p.h"
+#include "qaccessiblequickwidgetfactory_p.h"
 
 #include "private/qquickwindow_p.h"
 #include "private/qquickitem_p.h"
@@ -75,9 +76,16 @@
 
 QT_BEGIN_NAMESPACE
 
+QQuickWidgetOffscreenWindow::QQuickWidgetOffscreenWindow(QQuickWindowPrivate &dd, QQuickRenderControl *control)
+:QQuickWindow(dd, control)
+{
+    setTitle(QString::fromLatin1("Offscreen"));
+    setObjectName(QString::fromLatin1("QQuickOffScreenWindow"));
+}
+
 // override setVisble to prevent accidental offscreen window being created
 // by base class.
-class QQuickOffcreenWindowPrivate: public QQuickWindowPrivate {
+class QQuickWidgetOffscreenWindowPrivate: public QQuickWindowPrivate {
 public:
     void setVisible(bool visible) override {
         Q_Q(QWindow);
@@ -105,10 +113,8 @@ void QQuickWidgetPrivate::init(QQmlEngine* e)
     Q_Q(QQuickWidget);
 
     renderControl = new QQuickWidgetRenderControl(q);
-    offscreenWindow = new QQuickWindow(*new QQuickOffcreenWindowPrivate(),renderControl);
+    offscreenWindow = new QQuickWidgetOffscreenWindow(*new QQuickWidgetOffscreenWindowPrivate(), renderControl);
     offscreenWindow->setScreen(q->screen());
-    offscreenWindow->setTitle(QString::fromLatin1("Offscreen"));
-    offscreenWindow->setObjectName(QString::fromLatin1("QQuickOffScreenWindow"));
     // Do not call create() on offscreenWindow.
 
     // Check if the Software Adaptation is being used
@@ -139,6 +145,10 @@ void QQuickWidgetPrivate::init(QQmlEngine* e)
     QWidget::connect(offscreenWindow, &QQuickWindow::focusObjectChanged, q, &QQuickWidget::propagateFocusObjectChanged);
     QObject::connect(renderControl, SIGNAL(renderRequested()), q, SLOT(triggerUpdate()));
     QObject::connect(renderControl, SIGNAL(sceneChanged()), q, SLOT(triggerUpdate()));
+
+#if QT_CONFIG(accessibility)
+    QAccessible::installFactory(&qAccessibleQuickWidgetFactory);
+#endif
 }
 
 void QQuickWidgetPrivate::ensureEngine() const
diff --git a/src/quickwidgets/qquickwidget_p.h b/src/quickwidgets/qquickwidget_p.h
index 881f7f9220..1a946bcc71 100644
--- a/src/quickwidgets/qquickwidget_p.h
+++ b/src/quickwidgets/qquickwidget_p.h
@@ -148,6 +148,14 @@ public:
     bool forceFullUpdate;
 };
 
+class QQuickWidgetOffscreenWindow: public QQuickWindow
+{
+    Q_OBJECT
+
+public:
+    QQuickWidgetOffscreenWindow(QQuickWindowPrivate &dd, QQuickRenderControl *control);
+};
+
 QT_END_NAMESPACE
 
 #endif // QQuickWidget_P_H
diff --git a/src/quickwidgets/quickwidgets.pro b/src/quickwidgets/quickwidgets.pro
index 2438e577ae..f46deb54ac 100644
--- a/src/quickwidgets/quickwidgets.pro
+++ b/src/quickwidgets/quickwidgets.pro
@@ -7,9 +7,13 @@ DEFINES   += QT_NO_URL_CAST_FROM_STRING QT_NO_INTEGER_EVENT_COORDINATES QT_NO_FO
 HEADERS += \
     qquickwidget.h \
     qquickwidget_p.h \
-    qtquickwidgetsglobal.h
+    qtquickwidgetsglobal.h \
+    qaccessiblequickwidget.h \
+    qaccessiblequickwidgetfactory_p.h
 
 SOURCES += \
-    qquickwidget.cpp
+    qquickwidget.cpp \
+    qaccessiblequickwidget.cpp \
+    qaccessiblequickwidgetfactory.cpp
 
 load(qt_module)
-- 
2.40.0