Fix visibility regression when using offscreen window in qquickwidget

Since s 7ded77d in declarative we keep offscreen window in QQuickWidget
as not visible to make input delivery system happy and due to fact that
window is really not visible. However, this breaks some behavior
in case that "emulated" visibility is required.

Switch to track qwindow in case of rendercontrol instead of internal
offscreen window.

Task-number: QTBUG-79213
Change-Id: If98deb8c56c3ae3c053f4e4d21e6b3b69211a9c3
Reviewed-by: Christian Strømme <christian.stromme@qt.io>

1 files changed, 25 insertions, 11 deletions

diff --git a/src/webview/qquickviewcontroller.cpp b/src/webview/qquickviewcontroller.cpp
index 85050d6..11895d6 100644
--- a/src/webview/qquickviewcontroller.cpp
+++ b/src/webview/qquickviewcontroller.cpp
@@ -233,22 +233,36 @@ void QQuickViewController::geometryChanged(const QRectF &newGeometry, const QRec
 void QQuickViewController::onWindowChanged(QQuickWindow* window)
 {
     QQuickWindow *oldParent = qobject_cast<QQuickWindow *>(m_view->parentView());
-    if (oldParent != 0)
+    if (oldParent)
         oldParent->disconnect(this);
 
-    if (window != 0) {
-        connect(window, &QQuickWindow::widthChanged, this, &QQuickViewController::scheduleUpdatePolish);
-        connect(window, &QQuickWindow::heightChanged, this, &QQuickViewController::scheduleUpdatePolish);
-        connect(window, &QQuickWindow::xChanged, this, &QQuickViewController::scheduleUpdatePolish);
-        connect(window, &QQuickWindow::yChanged, this, &QQuickViewController::scheduleUpdatePolish);
-        connect(window, &QQuickWindow::sceneGraphInitialized, this, &QQuickViewController::scheduleUpdatePolish);
-        connect(window, &QQuickWindow::sceneGraphInvalidated, this, &QQuickViewController::onSceneGraphInvalidated);
-        connect(window, &QQuickWindow::visibleChanged, this, [this](bool visible) { m_view->setVisible(visible); });
+    if (!window) {
+        m_view->setParentView(nullptr);
+        return;
     }
 
-    // Check if there's an actual window available.
+    // Check if there's an actual native window available.
     QWindow *rw = QQuickRenderControl::renderWindowFor(window);
-    m_view->setParentView(rw ? rw : window);
+
+    if (rw) {
+        connect(rw, &QWindow::widthChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(rw, &QWindow::heightChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(rw, &QWindow::xChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(rw, &QWindow::yChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(rw, &QWindow::visibleChanged, this, [this](bool visible) { m_view->setVisible(visible); });
+        connect(window, &QQuickWindow::sceneGraphInitialized, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QQuickWindow::sceneGraphInvalidated, this, &QQuickViewController::onSceneGraphInvalidated);
+        m_view->setParentView(rw);
+    } else {
+        connect(window, &QWindow::widthChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QWindow::heightChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QWindow::xChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QWindow::yChanged, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QQuickWindow::sceneGraphInitialized, this, &QQuickViewController::scheduleUpdatePolish);
+        connect(window, &QQuickWindow::sceneGraphInvalidated, this, &QQuickViewController::onSceneGraphInvalidated);
+        connect(window, &QWindow::visibleChanged, this, [this](bool visible) { m_view->setVisible(visible); });
+        m_view->setParentView(window);
+    }
 }
 
 void QQuickViewController::onVisibleChanged()