Merge remote-tracking branch 'origin/5.12' into dev

 Conflicts:
	src/corelib/animation/qpropertyanimation.cpp
	src/gui/image/qicon.cpp
	tests/auto/widgets/itemviews/qtableview/tst_qtableview.cpp

Change-Id: I3698172b7b44ebb487cb38f50fd2c4a9f8a35b21

9 files changed, 646 insertions, 0 deletions

diff --git a/src/gui/doc/snippets/code/src_gui_accessible_qaccessible.cpp b/src/gui/doc/snippets/code/src_gui_accessible_qaccessible.cpp
index 98d40c94f9..2fd76d08c7 100644
--- a/src/gui/doc/snippets/code/src_gui_accessible_qaccessible.cpp
+++ b/src/gui/doc/snippets/code/src_gui_accessible_qaccessible.cpp
@@ -51,3 +51,21 @@
 //! [1]
 typedef QAccessibleInterface* myFactoryFunction(const QString &key, QObject *);
 //! [1]
+
+//! [2]
+void MyWidget::setFocus(Qt::FocusReason reason)
+{
+    // handle custom focus setting...
+    QAccessibleEvent event(f, QAccessible::Focus);
+    QAccessible::updateAccessibility(&event);
+}
+//! [2]
+
+//! [3]
+void *QAccessibleLineEdit::interface_cast(QAccessible::InterfaceType t)
+{
+    if (t == QAccessible::TextInterface)
+        return static_cast<QAccessibleTextInterface*>(this);
+    return QAccessibleWidget::interface_cast(t);
+}
+//! [3]
diff --git a/src/gui/doc/snippets/code/src_gui_math3d_qquaternion.cpp b/src/gui/doc/snippets/code/src_gui_math3d_qquaternion.cpp
new file mode 100644
index 0000000000..b5cd00d5aa
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_math3d_qquaternion.cpp
@@ -0,0 +1,46 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    QVector3D result = q.rotatedVector(vector);
+//! [0]
+
+//! [1]
+    QVector3D result = (q * QQuaternion(0, vector) * q.conjugated()).vector();
+//! [1]
diff --git a/src/gui/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp b/src/gui/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp
new file mode 100644
index 0000000000..4a4a6fe16d
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp
@@ -0,0 +1,49 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    QOpenGLBuffer buffer1(QOpenGLBuffer::IndexBuffer);
+    buffer1.create();
+
+    QOpenGLBuffer buffer2 = buffer1;
+//! [0]
+
+//! [1]
+    QOpenGLBuffer::release(QOpenGLBuffer::VertexBuffer);
+//! [1]
diff --git a/src/gui/doc/snippets/code/src_gui_opengl_qopengldebug.cpp b/src/gui/doc/snippets/code/src_gui_opengl_qopengldebug.cpp
new file mode 100644
index 0000000000..4ab84deb3e
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_opengl_qopengldebug.cpp
@@ -0,0 +1,89 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWidgets 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    GLenum error = GL_NO_ERROR;
+    do {
+        error = glGetError();
+        if (error != GL_NO_ERROR)
+            // handle the error
+    } while (error != GL_NO_ERROR);
+//! [0]
+
+//! [1]
+    QSurfaceFormat format;
+    // asks for a OpenGL 3.2 debug context using the Core profile
+    format.setMajorVersion(3);
+    format.setMinorVersion(2);
+    format.setProfile(QSurfaceFormat::CoreProfile);
+    format.setOption(QSurfaceFormat::DebugContext);
+
+    QOpenGLContext *context = new QOpenGLContext;
+    context->setFormat(format);
+    context->create();
+//! [1]
+
+//! [2]
+    QOpenGLContext *ctx = QOpenGLContext::currentContext();
+    QOpenGLDebugLogger *logger = new QOpenGLDebugLogger(this);
+
+    logger->initialize(); // initializes in the current context, i.e. ctx
+//! [2]
+
+//! [3]
+    ctx->hasExtension(QByteArrayLiteral("GL_KHR_debug"))
+//! [3]
+
+//! [4]
+    const QList<QOpenGLDebugMessage> messages = logger->loggedMessages();
+    for (const QOpenGLDebugMessage &message : messages)
+        qDebug() << message;
+//! [4]
+
+//! [5]
+    connect(logger, &QOpenGLDebugLogger::messageLogged, receiver, &LogHandler::handleLoggedMessage);
+    logger->startLogging();
+//! [5]
+
+//! [6]
+    QOpenGLDebugMessage message =
+        QOpenGLDebugMessage::createApplicationMessage(QStringLiteral("Custom message"));
+
+    logger->logMessage(message);
+//! [6]
diff --git a/src/gui/doc/snippets/code/src_gui_opengl_qopenglfunctions.cpp b/src/gui/doc/snippets/code/src_gui_opengl_qopenglfunctions.cpp
new file mode 100644
index 0000000000..68a20dcb7c
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_opengl_qopenglfunctions.cpp
@@ -0,0 +1,101 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    class MyGLWindow : public QWindow, protected QOpenGLFunctions
+    {
+        Q_OBJECT
+    public:
+        MyGLWindow(QScreen *screen = 0);
+
+    protected:
+        void initializeGL();
+        void paintGL();
+
+        QOpenGLContext *m_context;
+    };
+
+    MyGLWindow(QScreen *screen)
+      : QWindow(screen), QOpenGLWidget(parent)
+    {
+        setSurfaceType(OpenGLSurface);
+        create();
+
+        // Create an OpenGL context
+        m_context = new QOpenGLContext;
+        m_context->create();
+
+        // Setup scene and render it
+        initializeGL();
+        paintGL();
+    }
+
+    void MyGLWindow::initializeGL()
+    {
+        m_context->makeCurrent(this);
+        initializeOpenGLFunctions();
+    }
+//! [0]
+
+//! [1]
+    void MyGLWindow::paintGL()
+    {
+        m_context->makeCurrent(this);
+        glActiveTexture(GL_TEXTURE1);
+        glBindTexture(GL_TEXTURE_2D, textureId);
+        ...
+        m_context->swapBuffers(this);
+        m_context->doneCurrent();
+    }
+//! [1]
+
+//! [2]
+    QOpenGLFunctions glFuncs(QOpenGLContext::currentContext());
+    glFuncs.glActiveTexture(GL_TEXTURE1);
+//! [2]
+
+//! [3]
+    QOpenGLFunctions *glFuncs = QOpenGLContext::currentContext()->functions();
+    glFuncs->glActiveTexture(GL_TEXTURE1);
+//! [3]
+
+//! [4]
+    QOpenGLFunctions funcs(QOpenGLContext::currentContext());
+    bool npot = funcs.hasOpenGLFeature(QOpenGLFunctions::NPOTTextures);
+//! [4]
diff --git a/src/gui/doc/snippets/code/src_gui_util_qdesktopservices.cpp b/src/gui/doc/snippets/code/src_gui_util_qdesktopservices.cpp
index b48e9e8610..b9a8d8d90e 100644
--- a/src/gui/doc/snippets/code/src_gui_util_qdesktopservices.cpp
+++ b/src/gui/doc/snippets/code/src_gui_util_qdesktopservices.cpp
@@ -68,3 +68,31 @@ mailto:user@foo.com?subject=Test&body=Just a test
 //! [2]
 QDesktopServices::openUrl(QUrl("file:///C:/Documents and Settings/All Users/Desktop", QUrl::TolerantMode));
 //! [2]
+
+//! [3]
+<key>LSApplicationQueriesSchemes</key>
+<array>
+    <string>https</string>
+</array>
+//! [3]
+
+//! [4]
+<key>CFBundleURLTypes</key>
+<array>
+    <dict>
+        <key>CFBundleURLSchemes</key>
+        <array>
+            <string>myapp</string>
+        </array>
+    </dict>
+</array>
+//! [4]
+
+//! [5]
+QDesktopServices::storageLocation(QDesktopServices::DataLocation)
+//! [5]
+
+//! [6]
+QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation) +
+    "/data/organization/application"
+//! [6]
diff --git a/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanfunctions.cpp b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanfunctions.cpp
new file mode 100644
index 0000000000..77c5444df5
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanfunctions.cpp
@@ -0,0 +1,59 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    void Window::render()
+    {
+        QVulkanInstance *inst = vulkanInstance();
+        QVulkanFunctions *f = inst->functions();
+        ...
+        VkResult err = f->vkAllocateCommandBuffers(device, &cmdBufInfo, &cmdBuf);
+        ...
+    }
+//! [0]
+
+//! [1]
+    void Window::render()
+    {
+        QVulkanInstance *inst = vulkanInstance();
+        QVulkanDeviceFunctions *df = inst->deviceFunctions(device);
+        VkResult err = df->vkAllocateCommandBuffers(device, &cmdBufInfo, &cmdBuf);
+        ...
+    }
+//! [1]
diff --git a/src/gui/doc/snippets/code/src_gui_vulkan_qvulkaninstance.cpp b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkaninstance.cpp
new file mode 100644
index 0000000000..50afe7c0ff
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkaninstance.cpp
@@ -0,0 +1,135 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+    int main(int argc, char **argv)
+    {
+        QGuiApplication app(argc, argv);
+
+        QVulkanInstance inst;
+        if (!inst.create())
+            return 1;
+
+        ...
+        window->setVulkanInstance(&inst);
+        window->show();
+
+        return app.exec();
+    }
+//! [0]
+
+//! [1]
+    QVulkanInstance inst;
+
+    // Enable validation layer, if supported. Messages go to qDebug by default.
+    inst.setLayers(QByteArrayList() << "VK_LAYER_LUNARG_standard_validation");
+
+    bool ok = inst.create();
+    if (!ok)
+        ... // Vulkan not available
+    if (!inst.layers().contains("VK_LAYER_LUNARG_standard_validation"))
+        ... // validation layer not available
+//! [1]
+
+//! [2]
+    QVulkanInstance inst;
+
+    if (inst.supportedLayers().contains("VK_LAYER_LUNARG_standard_validation"))
+        ...
+
+    bool ok = inst.create();
+    ...
+//! [2]
+
+//! [3]
+    class VulkanWindow : public QWindow
+    {
+    public:
+        VulkanWindow() {
+            setSurfaceType(VulkanSurface);
+        }
+
+        void exposeEvent(QExposeEvent *) {
+            if (isExposed()) {
+                if (!m_initialized) {
+                    m_initialized = true;
+                    // initialize device, swapchain, etc.
+                    QVulkanInstance *inst = vulkanInstance();
+                    QVulkanFunctions *f = inst->functions();
+                    uint32_t devCount = 0;
+                    f->vkEnumeratePhysicalDevices(inst->vkInstance(), &devCount, nullptr);
+                    ...
+                    // build the first frame
+                    render();
+                }
+            }
+        }
+
+        bool event(QEvent *e) {
+            if (e->type == QEvent::UpdateRequest)
+                render();
+            return QWindow::event(e);
+        }
+
+        void render() {
+           ...
+           requestUpdate(); // render continuously
+        }
+
+    private:
+        bool m_initialized = false;
+    };
+
+    int main(int argc, char **argv)
+    {
+        QGuiApplication app(argc, argv);
+
+        QVulkanInstance inst;
+        if (!inst.create()) {
+            qWarning("Vulkan not available");
+            return 1;
+        }
+
+        VulkanWindow window;
+        window.showMaximized();
+
+        return app.exec();
+
+    }
+//! [3]
diff --git a/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanwindow.cpp b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanwindow.cpp
new file mode 100644
index 0000000000..65eca4a77f
--- /dev/null
+++ b/src/gui/doc/snippets/code/src_gui_vulkan_qvulkanwindow.cpp
@@ -0,0 +1,121 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtGui 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+  class VulkanRenderer : public QVulkanWindowRenderer
+  {
+  public:
+      VulkanRenderer(QVulkanWindow *w) : m_window(w) { }
+
+      void initResources() override
+      {
+          m_devFuncs = m_window->vulkanInstance()->deviceFunctions(m_window->device());
+          ...
+      }
+      void initSwapChainResources() override { ... }
+      void releaseSwapChainResources() override { ... }
+      void releaseResources() override { ... }
+
+      void startNextFrame() override
+      {
+          VkCommandBuffer cmdBuf = m_window->currentCommandBuffer();
+          ...
+          m_devFuncs->vkCmdBeginRenderPass(...);
+          ...
+          m_window->frameReady();
+      }
+
+  private:
+      QVulkanWindow *m_window;
+      QVulkanDeviceFunctions *m_devFuncs;
+  };
+
+  class VulkanWindow : public QVulkanWindow
+  {
+  public:
+      QVulkanWindowRenderer *createRenderer() override {
+          return new VulkanRenderer(this);
+      }
+  };
+
+  int main(int argc, char *argv[])
+  {
+      QGuiApplication app(argc, argv);
+
+      QVulkanInstance inst;
+      // enable the standard validation layers, when available
+      inst.setLayers(QByteArrayList() << "VK_LAYER_LUNARG_standard_validation");
+      if (!inst.create())
+          qFatal("Failed to create Vulkan instance: %d", inst.errorCode());
+
+      VulkanWindow w;
+      w.setVulkanInstance(&inst);
+      w.showMaximized();
+
+      return app.exec();
+  }
+//! [0]
+
+//! [1]
+    class Renderer {
+        ...
+        VkDescriptorBufferInfo m_uniformBufInfo[QVulkanWindow::MAX_CONCURRENT_FRAME_COUNT];
+    };
+
+    void Renderer::startNextFrame()
+    {
+        VkDescriptorBufferInfo &uniformBufInfo(m_uniformBufInfo[m_window->currentFrame()]);
+        ...
+    }
+//! [1]
+
+//! [2]
+    class Renderer {
+        ...
+        VkDescriptorBufferInfo m_uniformBufInfo[QVulkanWindow::MAX_CONCURRENT_FRAME_COUNT];
+    };
+
+    void Renderer::startNextFrame()
+    {
+        const int count = m_window->concurrentFrameCount();
+        for (int i = 0; i < count; ++i)
+            m_uniformBufInfo[i] = ...
+        ...
+    }
+//! [2]