2 files changed, 30 insertions, 2 deletions
diff --git a/src/widgets/kernel/qwindowcontainer.cpp b/src/widgets/kernel/qwindowcontainer.cpp
index bffc1f45f2..56114350d2 100644
--- a/src/widgets/kernel/qwindowcontainer.cpp
+++ b/src/widgets/kernel/qwindowcontainer.cpp
@@ -89,7 +89,7 @@ public:
 
     void updateUsesNativeWidgets()
     {
-        if (usesNativeWidgets || window->parent() == 0)
+        if (window->parent() == 0)
             return;
         Q_Q(QWindowContainer);
         if (q->internalWinId()) {
@@ -97,6 +97,7 @@ public:
             usesNativeWidgets = true;
             return;
         }
+        bool nativeWidgetSet = false;
         QWidget *p = q->parentWidget();
         while (p) {
             if (false
@@ -108,11 +109,12 @@ public:
 #endif
                     ) {
                 q->winId();
-                usesNativeWidgets = true;
+                nativeWidgetSet = true;
                 break;
             }
             p = p->parentWidget();
         }
+        usesNativeWidgets = nativeWidgetSet;
     }
 
     void markParentChain() {
diff --git a/tests/auto/widgets/kernel/qwindowcontainer/tst_qwindowcontainer.cpp b/tests/auto/widgets/kernel/qwindowcontainer/tst_qwindowcontainer.cpp
index 6ec1b754d0..a3e549aa50 100644
--- a/tests/auto/widgets/kernel/qwindowcontainer/tst_qwindowcontainer.cpp
+++ b/tests/auto/widgets/kernel/qwindowcontainer/tst_qwindowcontainer.cpp
@@ -74,6 +74,7 @@ private slots:
     void testOwnership();
     void testBehindTheScenesDeletion();
     void testUnparenting();
+    void testUnparentReparent();
     void testActivation();
     void testAncestorChange();
     void testDockWidget();
@@ -241,6 +242,31 @@ void tst_QWindowContainer::testUnparenting()
     QVERIFY(!window->isVisible());
 }
 
+void tst_QWindowContainer::testUnparentReparent()
+{
+    QWidget root;
+
+    QWindow *window = new QWindow();
+    QScopedPointer<QWidget> container(QWidget::createWindowContainer(window, &root));
+    container->setWindowTitle(QTest::currentTestFunction());
+    container->setGeometry(m_availableGeometry.x() + 100, m_availableGeometry.y() + 100, 200, 100);
+
+    root.show();
+
+    QVERIFY(QTest::qWaitForWindowExposed(&root));
+
+    QTRY_VERIFY(window->isVisible());
+
+    container->setParent(nullptr);
+    QTRY_VERIFY(!window->isVisible());
+
+    container->show();
+    QVERIFY(QTest::qWaitForWindowExposed(window));
+    QTRY_VERIFY(window->isVisible());
+
+    container->setParent(&root); // This should not crash (QTBUG-63168)
+}
+
 void tst_QWindowContainer::testAncestorChange()
 {
     QWidget root;