Pick up initial state of foreign windows instead of reflecting QWindow

A foreign window can be used both for embedding a Qt window into a
native window hierarchy, or for embedding a native window into a Qt
window hierarchy. In the former case, we should not modify the foreign
window in any way. Since the platform does not know anything about the
intended use case at the time of the foreign window creation, it should
avoid modifying the foreign window in any way, and should instead pick
up the foreign window state and reflect that through QWindow.

Pick-to: 6.5
Change-Id: Id2e39d101277ecebd656d615cea3e7f734a4b0a6
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 18 insertions, 12 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index 5976722c91..f29927751a 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -117,20 +117,26 @@ void QCocoaWindow::initialize()
     if (!m_view)
         m_view = [[QNSView alloc] initWithCocoaWindow:this];
 
-    // Compute the initial geometry based on the geometry set on the
-    // QWindow. This geometry has already been reflected to the
-    // QPlatformWindow in the constructor, so to ensure that the
-    // resulting setGeometry call does not think the geometry has
-    // already been applied, we reset the QPlatformWindow's view
-    // of the geometry first.
-    auto initialGeometry = QPlatformWindow::initialGeometry(window(),
-        windowGeometry(), defaultWindowWidth, defaultWindowHeight);
-    QPlatformWindow::d_ptr->rect = QRect();
-    setGeometry(initialGeometry);
+    if (!isForeignWindow()) {
+        // Compute the initial geometry based on the geometry set on the
+        // QWindow. This geometry has already been reflected to the
+        // QPlatformWindow in the constructor, so to ensure that the
+        // resulting setGeometry call does not think the geometry has
+        // already been applied, we reset the QPlatformWindow's view
+        // of the geometry first.
+        auto initialGeometry = QPlatformWindow::initialGeometry(window(),
+            windowGeometry(), defaultWindowWidth, defaultWindowHeight);
+        QPlatformWindow::d_ptr->rect = QRect();
+        setGeometry(initialGeometry);
+
+        setMask(QHighDpi::toNativeLocalRegion(window()->mask(), window()));
 
-    recreateWindowIfNeeded();
+    } else {
+        // Pick up essential foreign window state
+        QPlatformWindow::setGeometry(QRectF::fromCGRect(m_view.frame).toRect());
+    }
 
-    setMask(QHighDpi::toNativeLocalRegion(window()->mask(), window()));
+    recreateWindowIfNeeded();
 
     m_initialized = true;
 }