Update widget winId when screen changes

When a window's screen changes it may recreate the platform window.
In that case, update the winId in the widget to keep it in sync.

Task-number: QTBUG-40681
Change-Id: Iec815320214832bb63952de3a5bd1340a04dacd4
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index 65978ef562..8d1a24a4ec 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -9042,6 +9042,12 @@ bool QWidget::event(QEvent *event)
         event->ignore();
         break;
 #endif
+    case QEvent::ScreenChangeInternal:
+        if (const QTLWExtra *te = d->maybeTopData()) {
+            const QWindow *win = te->window;
+            d->setWinId((win && win->handle()) ? win->handle()->winId() : 0);
+        }
+        break;
 #ifndef QT_NO_PROPERTIES
     case QEvent::DynamicPropertyChange: {
         const QByteArray &propName = static_cast<QDynamicPropertyChangeEvent *>(event)->propertyName();