Fix crash on exit when centering Popup within Overlay in StackView item

If a Popup is centered within an Overlay, and that Overlay is destroyed
before the Popup, we must make sure centerIn is cleared so we don't try
to access a dangling pointer.

Fixes: QTBUG-84579
Change-Id: Icb2750f847f9d5710725bedc4d1c92bf4c122c03
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
(cherry picked from commit 04901b170e009d844232067446fdd56f270d155d)

1 files changed, 26 insertions, 0 deletions

diff --git a/src/quicktemplates2/qquickpopupanchors.cpp b/src/quicktemplates2/qquickpopupanchors.cpp
index 5acc2934..c7ac038d 100644
--- a/src/quicktemplates2/qquickpopupanchors.cpp
+++ b/src/quicktemplates2/qquickpopupanchors.cpp
@@ -47,6 +47,15 @@ QQuickPopupAnchors::QQuickPopupAnchors(QQuickPopup *popup)
     d->popup = popup;
 }
 
+QQuickPopupAnchors::~QQuickPopupAnchors()
+{
+    Q_D(const QQuickPopupAnchors);
+    if (d->centerIn) {
+        auto centerInPrivate = QQuickItemPrivate::get(d->centerIn);
+        centerInPrivate->removeItemChangeListener(this, QQuickItemPrivate::Destroyed);
+    }
+}
+
 QQuickItem *QQuickPopupAnchors::centerIn() const
 {
     Q_D(const QQuickPopupAnchors);
@@ -59,8 +68,20 @@ void QQuickPopupAnchors::setCenterIn(QQuickItem *item)
     if (item == d->centerIn)
         return;
 
+    if (d->centerIn) {
+        auto centerInPrivate = QQuickItemPrivate::get(d->centerIn);
+        centerInPrivate->removeItemChangeListener(this, QQuickItemPrivate::Destroyed);
+    }
+
     d->centerIn = item;
+
+    if (d->centerIn) {
+        auto centerInPrivate = QQuickItemPrivate::get(d->centerIn);
+        centerInPrivate->addItemChangeListener(this, QQuickItemPrivate::Destroyed);
+    }
+
     QQuickPopupPrivate::get(d->popup)->reposition();
+
     emit centerInChanged();
 }
 
@@ -69,4 +90,9 @@ void QQuickPopupAnchors::resetCenterIn()
     setCenterIn(nullptr);
 }
 
+void QQuickPopupAnchors::itemDestroyed(QQuickItem *)
+{
+    resetCenterIn();
+}
+
 QT_END_NAMESPACE