Ensure foreign window can be reparented out of contained window again

A foreign window embedded into a Qt hierarchy must also support
being removed from that window hierarchy.

Pick-to: 6.6
Change-Id: Id4d08079ff19d67a8989937bc72602e8bd14b31b
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 6 insertions, 4 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index 3fbc06a089..748b8ef1c6 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -1499,6 +1499,10 @@ void QCocoaWindow::recreateWindowIfNeeded()
     QPlatformWindow *parentWindow = QPlatformWindow::parent();
     auto *parentCocoaWindow = static_cast<QCocoaWindow *>(parentWindow);
 
+    QCocoaWindow *oldParentCocoaWindow = nullptr;
+    if (QNSView *qnsView = qnsview_cast(m_view.superview))
+        oldParentCocoaWindow = qnsView.platformWindow;
+
     if (isForeignWindow()) {
         // A foreign window is created as such, and can never move between being
         // foreign and not, so we don't need to get rid of any existing NSWindows,
@@ -1508,6 +1512,8 @@ void QCocoaWindow::recreateWindowIfNeeded()
         // We do however need to manage the parent relationship
         if (parentCocoaWindow)
             [parentCocoaWindow->m_view addSubview:m_view];
+        else if (oldParentCocoaWindow)
+            [m_view removeFromSuperview];
 
         return;
     }
@@ -1515,10 +1521,6 @@ void QCocoaWindow::recreateWindowIfNeeded()
     const bool isEmbeddedView = isEmbedded();
     RecreationReasons recreateReason = RecreationNotNeeded;
 
-    QCocoaWindow *oldParentCocoaWindow = nullptr;
-    if (QNSView *qnsView = qnsview_cast(m_view.superview))
-        oldParentCocoaWindow = qnsView.platformWindow;
-
     if (parentWindow != oldParentCocoaWindow)
          recreateReason |= ParentChanged;