Fix JS ownership of model and delegate properties in QtQuick item views

When assigning a JS owned model or delegate to an item view, we must
ensure that they stay alive as long as the item view. This happens
easily for example when doing something like

    delegate: Qt.createComponent(...)

This patch takes the minimally invasive approach by changing the QObject
parent of such objects.

Task-number: QTBUG-50319
Task-number: QTBUG-51620
Change-Id: Ie6384b8dd93dcdc62d49f64b38173b3fc4ffd3b3
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

2 files changed, 5 insertions, 5 deletions

diff --git a/src/qml/util/qqmladaptormodel.cpp b/src/qml/util/qqmladaptormodel.cpp
index c430074f56..15844017aa 100644
--- a/src/qml/util/qqmladaptormodel.cpp
+++ b/src/qml/util/qqmladaptormodel.cpp
@@ -956,7 +956,7 @@ void QQmlAdaptorModel::setModel(const QVariant &variant, QQmlDelegateModel *vdm,
     list.setList(variant, engine);
 
     if (QObject *object = qvariant_cast<QObject *>(list.list())) {
-        setObject(object);
+        setObject(object, vdm);
         if (QAbstractItemModel *model = qobject_cast<QAbstractItemModel *>(object)) {
             accessors = new VDMAbstractItemModelDataType(this);
 
@@ -978,14 +978,14 @@ void QQmlAdaptorModel::setModel(const QVariant &variant, QQmlDelegateModel *vdm,
             accessors = new VDMObjectDelegateDataType;
         }
     } else if (list.type() == QQmlListAccessor::ListProperty) {
-        setObject(static_cast<const QQmlListReference *>(variant.constData())->object());
+        setObject(static_cast<const QQmlListReference *>(variant.constData())->object(), vdm);
         accessors = new VDMObjectDelegateDataType;
     } else if (list.type() != QQmlListAccessor::Invalid
             && list.type() != QQmlListAccessor::Instance) { // Null QObject
-        setObject(nullptr);
+        setObject(nullptr, vdm);
         accessors = &qt_vdm_list_accessors;
     } else {
-        setObject(nullptr);
+        setObject(nullptr, vdm);
         accessors = &qt_vdm_null_accessors;
     }
 }
diff --git a/src/qml/util/qqmladaptormodel_p.h b/src/qml/util/qqmladaptormodel_p.h
index b706fcb5f2..3b2d180ca7 100644
--- a/src/qml/util/qqmladaptormodel_p.h
+++ b/src/qml/util/qqmladaptormodel_p.h
@@ -68,7 +68,7 @@ class QQmlDelegateModel;
 class QQmlDelegateModelItem;
 class QQmlDelegateModelItemMetaType;
 
-class QQmlAdaptorModel : public QQmlGuard<QObject>
+class QQmlAdaptorModel : public QQmlStrongJSQObjectReference<QObject>
 {
 public:
     class Accessors