Move QQuickStackElement into its own files

Change-Id: I4fce147f125d4641e1eb3a6534f57d68000dbfc7
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

6 files changed, 403 insertions, 292 deletions

diff --git a/src/quicktemplates2/qquickstackelement.cpp b/src/quicktemplates2/qquickstackelement.cpp
new file mode 100644
index 00000000..b90774a2
--- /dev/null
+++ b/src/quicktemplates2/qquickstackelement.cpp
@@ -0,0 +1,292 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Quick Templates 2 module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://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.LGPLv3 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.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 later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qquickstackelement_p_p.h"
+#include "qquickstackview_p_p.h"
+
+#include <QtQml/qqmlinfo.h>
+#include <QtQml/qqmlengine.h>
+#include <QtQml/qqmlcomponent.h>
+#include <QtQml/qqmlincubator.h>
+#include <QtQml/private/qv4qobjectwrapper_p.h>
+#include <QtQml/private/qqmlcomponent_p.h>
+#include <QtQml/private/qqmlengine_p.h>
+
+QT_BEGIN_NAMESPACE
+
+static QQuickStackAttached *attachedStackObject(QQuickStackElement *element)
+{
+    QQuickStackAttached *attached = qobject_cast<QQuickStackAttached *>(qmlAttachedPropertiesObject<QQuickStackView>(element->item, false));
+    if (attached)
+        QQuickStackAttachedPrivate::get(attached)->element = element;
+    return attached;
+}
+
+class QQuickStackIncubator : public QQmlIncubator
+{
+public:
+    QQuickStackIncubator(QQuickStackElement *element) : QQmlIncubator(Synchronous), element(element) { }
+
+protected:
+    void setInitialState(QObject *object) override { element->incubate(object); }
+
+private:
+    QQuickStackElement *element;
+};
+
+QQuickStackElement::QQuickStackElement() : QQuickItemViewTransitionableItem(nullptr),
+    index(-1), init(false), removal(false), ownItem(false), ownComponent(false), widthValid(false), heightValid(false),
+    context(nullptr), component(nullptr), view(nullptr),
+    status(QQuickStackView::Inactive)
+{
+}
+
+QQuickStackElement::~QQuickStackElement()
+{
+    if (item)
+        QQuickItemPrivate::get(item)->removeItemChangeListener(this, QQuickItemPrivate::Destroyed);
+
+    if (ownComponent)
+        delete component;
+
+    QQuickStackAttached *attached = attachedStackObject(this);
+    if (item) {
+        if (ownItem) {
+            item->setParentItem(nullptr);
+            item->deleteLater();
+            item = nullptr;
+        } else {
+            item->setVisible(false);
+            if (!widthValid)
+                item->resetWidth();
+            if (!heightValid)
+                item->resetHeight();
+            if (item->parentItem() != originalParent) {
+                item->setParentItem(originalParent);
+            } else {
+                if (attached)
+                    QQuickStackAttachedPrivate::get(attached)->itemParentChanged(item, nullptr);
+            }
+        }
+    }
+
+    if (attached)
+        emit attached->removed();
+
+    delete context;
+}
+
+QQuickStackElement *QQuickStackElement::fromString(const QString &str, QQuickStackView *view)
+{
+    QQuickStackElement *element = new QQuickStackElement;
+    element->component = new QQmlComponent(qmlEngine(view), QUrl(str), view);
+    element->ownComponent = true;
+    return element;
+}
+
+QQuickStackElement *QQuickStackElement::fromObject(QObject *object, QQuickStackView *view)
+{
+    Q_UNUSED(view);
+    QQuickStackElement *element = new QQuickStackElement;
+    element->component = qobject_cast<QQmlComponent *>(object);
+    element->item = qobject_cast<QQuickItem *>(object);
+    if (element->item)
+        element->originalParent = element->item->parentItem();
+    return element;
+}
+
+bool QQuickStackElement::load(QQuickStackView *parent)
+{
+    setView(parent);
+    if (!item) {
+        ownItem = true;
+
+        if (component->isLoading()) {
+            QObject::connect(component, &QQmlComponent::statusChanged, [this](QQmlComponent::Status status) {
+                if (status == QQmlComponent::Ready)
+                    load(view);
+                else if (status == QQmlComponent::Error)
+                    qWarning() << qPrintable(component->errorString().trimmed());
+            });
+            return true;
+        }
+
+        QQmlContext *creationContext = component->creationContext();
+        if (!creationContext)
+            creationContext = qmlContext(parent);
+        context = new QQmlContext(creationContext);
+        context->setContextObject(parent);
+
+        QQuickStackIncubator incubator(this);
+        component->create(incubator, context);
+        if (component->isError())
+            qWarning() << qPrintable(component->errorString().trimmed());
+    } else {
+        initialize();
+    }
+    return item;
+}
+
+void QQuickStackElement::incubate(QObject *object)
+{
+    item = qmlobject_cast<QQuickItem *>(object);
+    if (item) {
+        QQmlEngine::setObjectOwnership(item, QQmlEngine::CppOwnership);
+        item->setParent(view);
+        initialize();
+    }
+}
+
+void QQuickStackElement::initialize()
+{
+    if (!item || init)
+        return;
+
+    QQuickItemPrivate *p = QQuickItemPrivate::get(item);
+    if (!(widthValid = p->widthValid))
+        item->setWidth(view->width());
+    if (!(heightValid = p->heightValid))
+        item->setHeight(view->height());
+    item->setParentItem(view);
+    p->addItemChangeListener(this, QQuickItemPrivate::Destroyed);
+
+    if (!properties.isUndefined()) {
+        QQmlEngine *engine = qmlEngine(view);
+        Q_ASSERT(engine);
+        QV4::ExecutionEngine *v4 = QQmlEnginePrivate::getV4Engine(engine);
+        Q_ASSERT(v4);
+        QV4::Scope scope(v4);
+        QV4::ScopedValue ipv(scope, properties.value());
+        QV4::Scoped<QV4::QmlContext> qmlContext(scope, qmlCallingContext.value());
+        QV4::ScopedValue qmlObject(scope, QV4::QObjectWrapper::wrap(v4, item));
+        QQmlComponentPrivate::setInitialProperties(v4, qmlContext, qmlObject, ipv);
+        properties.clear();
+    }
+
+    init = true;
+}
+
+void QQuickStackElement::setIndex(int value)
+{
+    if (index == value)
+        return;
+
+    index = value;
+    QQuickStackAttached *attached = attachedStackObject(this);
+    if (attached)
+        emit attached->indexChanged();
+}
+
+void QQuickStackElement::setView(QQuickStackView *value)
+{
+    if (view == value)
+        return;
+
+    view = value;
+    QQuickStackAttached *attached = attachedStackObject(this);
+    if (attached)
+        emit attached->viewChanged();
+}
+
+void QQuickStackElement::setStatus(QQuickStackView::Status value)
+{
+    if (status == value)
+        return;
+
+    status = value;
+    QQuickStackAttached *attached = attachedStackObject(this);
+    if (!attached)
+        return;
+
+    switch (value) {
+    case QQuickStackView::Inactive:
+        emit attached->deactivated();
+        break;
+    case QQuickStackView::Deactivating:
+        emit attached->deactivating();
+        break;
+    case QQuickStackView::Activating:
+        emit attached->activating();
+        break;
+    case QQuickStackView::Active:
+        emit attached->activated();
+        break;
+    default:
+        Q_UNREACHABLE();
+        break;
+    }
+
+    emit attached->statusChanged();
+}
+
+void QQuickStackElement::transitionNextReposition(QQuickItemViewTransitioner *transitioner, QQuickItemViewTransitioner::TransitionType type, bool asTarget)
+{
+    if (transitioner)
+        transitioner->transitionNextReposition(this, type, asTarget);
+}
+
+bool QQuickStackElement::prepareTransition(QQuickItemViewTransitioner *transitioner, const QRectF &viewBounds)
+{
+    if (transitioner) {
+        if (item) {
+            QQuickAnchors *anchors = QQuickItemPrivate::get(item)->_anchors;
+            // TODO: expose QQuickAnchorLine so we can test for other conflicting anchors
+            if (anchors && (anchors->fill() || anchors->centerIn()))
+                qmlInfo(item) << "StackView has detected conflicting anchors. Transitions may not execute properly.";
+        }
+
+        // TODO: add force argument to QQuickItemViewTransitionableItem::prepareTransition()?
+        nextTransitionToSet = true;
+        nextTransitionFromSet = true;
+        nextTransitionFrom += QPointF(1, 1);
+        return QQuickItemViewTransitionableItem::prepareTransition(transitioner, index, viewBounds);
+    }
+    return false;
+}
+
+void QQuickStackElement::startTransition(QQuickItemViewTransitioner *transitioner, QQuickStackView::Status status)
+{
+    setStatus(status);
+    if (transitioner)
+        QQuickItemViewTransitionableItem::startTransition(transitioner, index);
+}
+
+void QQuickStackElement::itemDestroyed(QQuickItem *)
+{
+    item = nullptr;
+}
+
+QT_END_NAMESPACE
diff --git a/src/quicktemplates2/qquickstackelement_p_p.h b/src/quicktemplates2/qquickstackelement_p_p.h
new file mode 100644
index 00000000..638006a5
--- /dev/null
+++ b/src/quicktemplates2/qquickstackelement_p_p.h
@@ -0,0 +1,105 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the Qt Quick Templates 2 module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL3$
+** 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 http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://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.LGPLv3 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.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 later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQUICKSTACKELEMENT_P_P_H
+#define QQUICKSTACKELEMENT_P_P_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.
+//
+
+#include <QtQuickTemplates2/private/qquickstackview_p.h>
+#include <QtQuickTemplates2/private/qquickcontrol_p_p.h>
+#include <QtQuick/private/qquickitemviewtransition_p.h>
+#include <QtQuick/private/qquickitemchangelistener_p.h>
+#include <QtQml/private/qv4persistent_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QQmlContext;
+class QQmlComponent;
+struct QQuickStackTransition;
+
+class QQuickStackElement : public QQuickItemViewTransitionableItem, public QQuickItemChangeListener
+{
+    QQuickStackElement();
+
+public:
+    ~QQuickStackElement();
+
+    static QQuickStackElement *fromString(const QString &str, QQuickStackView *view);
+    static QQuickStackElement *fromObject(QObject *object, QQuickStackView *view);
+
+    bool load(QQuickStackView *parent);
+    void incubate(QObject *object);
+    void initialize();
+
+    void setIndex(int index);
+    void setView(QQuickStackView *view);
+    void setStatus(QQuickStackView::Status status);
+
+    void transitionNextReposition(QQuickItemViewTransitioner *transitioner, QQuickItemViewTransitioner::TransitionType type, bool asTarget);
+    bool prepareTransition(QQuickItemViewTransitioner *transitioner, const QRectF &viewBounds);
+    void startTransition(QQuickItemViewTransitioner *transitioner, QQuickStackView::Status status);
+
+    void itemDestroyed(QQuickItem *item) override;
+
+    int index;
+    bool init;
+    bool removal;
+    bool ownItem;
+    bool ownComponent;
+    bool widthValid;
+    bool heightValid;
+    QQmlContext *context;
+    QQmlComponent *component;
+    QQuickStackView *view;
+    QPointer<QQuickItem> originalParent;
+    QQuickStackView::Status status;
+    QV4::PersistentValue properties;
+    QV4::PersistentValue qmlCallingContext;
+};
+
+QT_END_NAMESPACE
+
+#endif // QQUICKSTACKELEMENT_P_P_H
diff --git a/src/quicktemplates2/qquickstackview.cpp b/src/quicktemplates2/qquickstackview.cpp
index c4bba4c8..3ccb85d1 100644
--- a/src/quicktemplates2/qquickstackview.cpp
+++ b/src/quicktemplates2/qquickstackview.cpp
@@ -36,6 +36,7 @@
 
 #include "qquickstackview_p.h"
 #include "qquickstackview_p_p.h"
+#include "qquickstackelement_p_p.h"
 
 #include <QtQml/qjsvalue.h>
 #include <QtQml/qqmlengine.h>
diff --git a/src/quicktemplates2/qquickstackview_p.cpp b/src/quicktemplates2/qquickstackview_p.cpp
index 2657695d..2842eeb4 100644
--- a/src/quicktemplates2/qquickstackview_p.cpp
+++ b/src/quicktemplates2/qquickstackview_p.cpp
@@ -35,263 +35,15 @@
 ****************************************************************************/
 
 #include "qquickstackview_p_p.h"
+#include "qquickstackelement_p_p.h"
 
-#include <QtQml/qqmlinfo.h>
 #include <QtQml/qqmllist.h>
-#include <QtQml/qqmlengine.h>
-#include <QtQml/qqmlcomponent.h>
-#include <QtQml/qqmlincubator.h>
 #include <QtQml/private/qv4qobjectwrapper_p.h>
-#include <QtQml/private/qqmlcomponent_p.h>
-#include <QtQml/private/qqmlengine_p.h>
 #include <QtQuick/private/qquickanimation_p.h>
 #include <QtQuick/private/qquicktransition_p.h>
-#include <QtQuick/private/qquickitemviewtransition_p.h>
 
 QT_BEGIN_NAMESPACE
 
-static QQuickStackAttached *attachedStackObject(QQuickStackElement *element)
-{
-    QQuickStackAttached *attached = qobject_cast<QQuickStackAttached *>(qmlAttachedPropertiesObject<QQuickStackView>(element->item, false));
-    if (attached)
-        QQuickStackAttachedPrivate::get(attached)->element = element;
-    return attached;
-}
-
-class QQuickStackIncubator : public QQmlIncubator
-{
-public:
-    QQuickStackIncubator(QQuickStackElement *element) : QQmlIncubator(Synchronous), element(element) { }
-
-protected:
-    void setInitialState(QObject *object) override { element->incubate(object); }
-
-private:
-    QQuickStackElement *element;
-};
-
-QQuickStackElement::QQuickStackElement() : QQuickItemViewTransitionableItem(nullptr),
-    index(-1), init(false), removal(false), ownItem(false), ownComponent(false), widthValid(false), heightValid(false),
-    context(nullptr), component(nullptr), view(nullptr),
-    status(QQuickStackView::Inactive)
-{
-}
-
-QQuickStackElement::~QQuickStackElement()
-{
-    if (item)
-        QQuickItemPrivate::get(item)->removeItemChangeListener(this, QQuickItemPrivate::Destroyed);
-
-    if (ownComponent)
-        delete component;
-
-    QQuickStackAttached *attached = attachedStackObject(this);
-    if (item) {
-        if (ownItem) {
-            item->setParentItem(nullptr);
-            item->deleteLater();
-            item = nullptr;
-        } else {
-            item->setVisible(false);
-            if (!widthValid)
-                item->resetWidth();
-            if (!heightValid)
-                item->resetHeight();
-            if (item->parentItem() != originalParent) {
-                item->setParentItem(originalParent);
-            } else {
-                if (attached)
-                    QQuickStackAttachedPrivate::get(attached)->itemParentChanged(item, nullptr);
-            }
-        }
-    }
-
-    if (attached)
-        emit attached->removed();
-
-    delete context;
-}
-
-QQuickStackElement *QQuickStackElement::fromString(const QString &str, QQuickStackView *view)
-{
-    QQuickStackElement *element = new QQuickStackElement;
-    element->component = new QQmlComponent(qmlEngine(view), QUrl(str), view);
-    element->ownComponent = true;
-    return element;
-}
-
-QQuickStackElement *QQuickStackElement::fromObject(QObject *object, QQuickStackView *view)
-{
-    Q_UNUSED(view);
-    QQuickStackElement *element = new QQuickStackElement;
-    element->component = qobject_cast<QQmlComponent *>(object);
-    element->item = qobject_cast<QQuickItem *>(object);
-    if (element->item)
-        element->originalParent = element->item->parentItem();
-    return element;
-}
-
-bool QQuickStackElement::load(QQuickStackView *parent)
-{
-    setView(parent);
-    if (!item) {
-        ownItem = true;
-
-        if (component->isLoading()) {
-            QObject::connect(component, &QQmlComponent::statusChanged, [this](QQmlComponent::Status status) {
-                if (status == QQmlComponent::Ready)
-                    load(view);
-                else if (status == QQmlComponent::Error)
-                    qWarning() << qPrintable(component->errorString().trimmed());
-            });
-            return true;
-        }
-
-        QQmlContext *creationContext = component->creationContext();
-        if (!creationContext)
-            creationContext = qmlContext(parent);
-        context = new QQmlContext(creationContext);
-        context->setContextObject(parent);
-
-        QQuickStackIncubator incubator(this);
-        component->create(incubator, context);
-        if (component->isError())
-            qWarning() << qPrintable(component->errorString().trimmed());
-    } else {
-        initialize();
-    }
-    return item;
-}
-
-void QQuickStackElement::incubate(QObject *object)
-{
-    item = qmlobject_cast<QQuickItem *>(object);
-    if (item) {
-        QQmlEngine::setObjectOwnership(item, QQmlEngine::CppOwnership);
-        item->setParent(view);
-        initialize();
-    }
-}
-
-void QQuickStackElement::initialize()
-{
-    if (!item || init)
-        return;
-
-    QQuickItemPrivate *p = QQuickItemPrivate::get(item);
-    if (!(widthValid = p->widthValid))
-        item->setWidth(view->width());
-    if (!(heightValid = p->heightValid))
-        item->setHeight(view->height());
-    item->setParentItem(view);
-    p->addItemChangeListener(this, QQuickItemPrivate::Destroyed);
-
-    if (!properties.isUndefined()) {
-        QQmlEngine *engine = qmlEngine(view);
-        Q_ASSERT(engine);
-        QV4::ExecutionEngine *v4 = QQmlEnginePrivate::getV4Engine(engine);
-        Q_ASSERT(v4);
-        QV4::Scope scope(v4);
-        QV4::ScopedValue ipv(scope, properties.value());
-        QV4::Scoped<QV4::QmlContext> qmlContext(scope, qmlCallingContext.value());
-        QV4::ScopedValue qmlObject(scope, QV4::QObjectWrapper::wrap(v4, item));
-        QQmlComponentPrivate::setInitialProperties(v4, qmlContext, qmlObject, ipv);
-        properties.clear();
-    }
-
-    init = true;
-}
-
-void QQuickStackElement::setIndex(int value)
-{
-    if (index == value)
-        return;
-
-    index = value;
-    QQuickStackAttached *attached = attachedStackObject(this);
-    if (attached)
-        emit attached->indexChanged();
-}
-
-void QQuickStackElement::setView(QQuickStackView *value)
-{
-    if (view == value)
-        return;
-
-    view = value;
-    QQuickStackAttached *attached = attachedStackObject(this);
-    if (attached)
-        emit attached->viewChanged();
-}
-
-void QQuickStackElement::setStatus(QQuickStackView::Status value)
-{
-    if (status == value)
-        return;
-
-    status = value;
-    QQuickStackAttached *attached = attachedStackObject(this);
-    if (!attached)
-        return;
-
-    switch (value) {
-    case QQuickStackView::Inactive:
-        emit attached->deactivated();
-        break;
-    case QQuickStackView::Deactivating:
-        emit attached->deactivating();
-        break;
-    case QQuickStackView::Activating:
-        emit attached->activating();
-        break;
-    case QQuickStackView::Active:
-        emit attached->activated();
-        break;
-    default:
-        Q_UNREACHABLE();
-        break;
-    }
-
-    emit attached->statusChanged();
-}
-
-void QQuickStackElement::transitionNextReposition(QQuickItemViewTransitioner *transitioner, QQuickItemViewTransitioner::TransitionType type, bool asTarget)
-{
-    if (transitioner)
-        transitioner->transitionNextReposition(this, type, asTarget);
-}
-
-bool QQuickStackElement::prepareTransition(QQuickItemViewTransitioner *transitioner, const QRectF &viewBounds)
-{
-    if (transitioner) {
-        if (item) {
-            QQuickAnchors *anchors = QQuickItemPrivate::get(item)->_anchors;
-            // TODO: expose QQuickAnchorLine so we can test for other conflicting anchors
-            if (anchors && (anchors->fill() || anchors->centerIn()))
-                qmlInfo(item) << "StackView has detected conflicting anchors. Transitions may not execute properly.";
-        }
-
-        // TODO: add force argument to QQuickItemViewTransitionableItem::prepareTransition()?
-        nextTransitionToSet = true;
-        nextTransitionFromSet = true;
-        nextTransitionFrom += QPointF(1, 1);
-        return QQuickItemViewTransitionableItem::prepareTransition(transitioner, index, viewBounds);
-    }
-    return false;
-}
-
-void QQuickStackElement::startTransition(QQuickItemViewTransitioner *transitioner, QQuickStackView::Status status)
-{
-    setStatus(status);
-    if (transitioner)
-        QQuickItemViewTransitionableItem::startTransition(transitioner, index);
-}
-
-void QQuickStackElement::itemDestroyed(QQuickItem *)
-{
-    item = nullptr;
-}
-
 QQuickStackViewPrivate::QQuickStackViewPrivate() : busy(false), currentItem(nullptr), transitioner(nullptr)
 {
 }
diff --git a/src/quicktemplates2/qquickstackview_p_p.h b/src/quicktemplates2/qquickstackview_p_p.h
index 5b3b1445..806ce747 100644
--- a/src/quicktemplates2/qquickstackview_p_p.h
+++ b/src/quicktemplates2/qquickstackview_p_p.h
@@ -52,54 +52,13 @@
 #include <QtQuickTemplates2/private/qquickcontrol_p_p.h>
 #include <QtQuick/private/qquickitemviewtransition_p.h>
 #include <QtQuick/private/qquickitemchangelistener_p.h>
-#include <QtQml/private/qv4persistent_p.h>
+#include <QtQml/private/qv4value_p.h>
 
 QT_BEGIN_NAMESPACE
 
-class QQmlContext;
-class QQmlComponent;
+class QQuickStackElement;
 struct QQuickStackTransition;
 
-class QQuickStackElement : public QQuickItemViewTransitionableItem, public QQuickItemChangeListener
-{
-    QQuickStackElement();
-
-public:
-    ~QQuickStackElement();
-
-    static QQuickStackElement *fromString(const QString &str, QQuickStackView *view);
-    static QQuickStackElement *fromObject(QObject *object, QQuickStackView *view);
-
-    bool load(QQuickStackView *parent);
-    void incubate(QObject *object);
-    void initialize();
-
-    void setIndex(int index);
-    void setView(QQuickStackView *view);
-    void setStatus(QQuickStackView::Status status);
-
-    void transitionNextReposition(QQuickItemViewTransitioner *transitioner, QQuickItemViewTransitioner::TransitionType type, bool asTarget);
-    bool prepareTransition(QQuickItemViewTransitioner *transitioner, const QRectF &viewBounds);
-    void startTransition(QQuickItemViewTransitioner *transitioner, QQuickStackView::Status status);
-
-    void itemDestroyed(QQuickItem *item) override;
-
-    int index;
-    bool init;
-    bool removal;
-    bool ownItem;
-    bool ownComponent;
-    bool widthValid;
-    bool heightValid;
-    QQmlContext *context;
-    QQmlComponent *component;
-    QQuickStackView *view;
-    QPointer<QQuickItem> originalParent;
-    QQuickStackView::Status status;
-    QV4::PersistentValue properties;
-    QV4::PersistentValue qmlCallingContext;
-};
-
 class QQuickStackViewPrivate : public QQuickControlPrivate, public QQuickItemViewTransitionChangeListener
 {
     Q_DECLARE_PUBLIC(QQuickStackView)
diff --git a/src/quicktemplates2/quicktemplates2.pri b/src/quicktemplates2/quicktemplates2.pri
index 242a6669..69671225 100644
--- a/src/quicktemplates2/quicktemplates2.pri
+++ b/src/quicktemplates2/quicktemplates2.pri
@@ -54,6 +54,7 @@ HEADERS += \
     $$PWD/qquickscrollindicator_p.h \
     $$PWD/qquickslider_p.h \
     $$PWD/qquickspinbox_p.h \
+    $$PWD/qquickstackelement_p_p.h \
     $$PWD/qquickstackview_p.h \
     $$PWD/qquickstackview_p_p.h \
     $$PWD/qquickswipedelegate_p.h \
@@ -114,6 +115,7 @@ SOURCES += \
     $$PWD/qquickscrollindicator.cpp \
     $$PWD/qquickslider.cpp \
     $$PWD/qquickspinbox.cpp \
+    $$PWD/qquickstackelement.cpp \
     $$PWD/qquickstackview.cpp \
     $$PWD/qquickstackview_p.cpp \
     $$PWD/qquickswipedelegate.cpp \