QWidget/Win: fix restoreGeometry() from fullscreen mode

When turning off fullscreen mode and restoring the widget's geometry
we must inform the QWindow about the geometry change synchronously.
Otherwise QWidget::geometry() will return the old value.

Using the same technique for the state transition to fullscreen mode
without sending a separate resize event.

Autotest: tst_QWidget::saveRestoreGeometry
Task-number: QTBUG-26421

Change-Id: I869e36cd302d9a94e398f48949ab3cb7ee9cdf51
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@nokia.com>

3 files changed, 14 insertions, 5 deletions

diff --git a/src/plugins/platforms/windows/qwindowswindow.cpp b/src/plugins/platforms/windows/qwindowswindow.cpp
index bc886f077f..85c8a6951a 100644
--- a/src/plugins/platforms/windows/qwindowswindow.cpp
+++ b/src/plugins/platforms/windows/qwindowswindow.cpp
@@ -993,7 +993,10 @@ void QWindowsWindow::handleGeometryChange()
 {
     m_data.geometry = geometry_sys();
     QPlatformWindow::setGeometry(m_data.geometry);
-    QWindowSystemInterface::handleGeometryChange(window(), m_data.geometry);
+    if (testFlag(SynchronousGeometryChangeEvent))
+        QWindowSystemInterface::handleSynchronousGeometryChange(window(), m_data.geometry);
+    else
+        QWindowSystemInterface::handleGeometryChange(window(), m_data.geometry);
 
     if (QWindowsContext::verboseEvents || QWindowsContext::verboseWindows)
         qDebug() << __FUNCTION__ << this << window() << m_data.geometry;
@@ -1246,7 +1249,11 @@ void QWindowsWindow::setWindowState_sys(Qt::WindowState newState)
             UINT swpf = SWP_FRAMECHANGED;
             if (newStates & Qt::WindowActive)
                 swpf |= SWP_NOACTIVATE;
+            const bool wasSync = testFlag(SynchronousGeometryChangeEvent);
+            setFlag(SynchronousGeometryChangeEvent);
             SetWindowPos(m_data.hwnd, HWND_TOP, r.left(), r.top(), r.width(), r.height(), swpf);
+            if (!wasSync)
+                clearFlag(SynchronousGeometryChangeEvent);
             QWindowSystemInterface::handleSynchronousGeometryChange(window(), r);
         } else if (!(newStates & Qt::WindowMinimized)) {
             // Restore saved state.
@@ -1260,8 +1267,12 @@ void QWindowsWindow::setWindowState_sys(Qt::WindowState newState)
                 swpf |= SWP_NOACTIVATE;
             if (!m_savedFrameGeometry.isValid())
                 swpf |= SWP_NOSIZE | SWP_NOMOVE;
+            const bool wasSync = testFlag(SynchronousGeometryChangeEvent);
+            setFlag(SynchronousGeometryChangeEvent);
             SetWindowPos(m_data.hwnd, 0, m_savedFrameGeometry.x(), m_savedFrameGeometry.y(),
                          m_savedFrameGeometry.width(), m_savedFrameGeometry.height(), swpf);
+            if (!wasSync)
+                clearFlag(SynchronousGeometryChangeEvent);
             // preserve maximized state
             if (visible)
                 ShowWindow(m_data.hwnd, (newStates & Qt::WindowMaximized) ? max : normal);
diff --git a/src/plugins/platforms/windows/qwindowswindow.h b/src/plugins/platforms/windows/qwindowswindow.h
index 176a02bc36..b2b33302f6 100644
--- a/src/plugins/platforms/windows/qwindowswindow.h
+++ b/src/plugins/platforms/windows/qwindowswindow.h
@@ -124,7 +124,8 @@ public:
         OpenGlPixelFormatInitialized = 0x40,
         BlockedByModal = 0x80,
         SizeGripOperation = 0x100,
-        FrameStrutEventsEnabled = 0x200
+        FrameStrutEventsEnabled = 0x200,
+        SynchronousGeometryChangeEvent = 0x400
     };
 
     struct WindowData
diff --git a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
index caaabe0e76..cf65556a1a 100644
--- a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
+++ b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
@@ -2945,9 +2945,6 @@ void tst_QWidget::saveRestoreGeometry()
         QVERIFY(widget.restoreGeometry(savedGeometry));
         QTest::qWait(120);
         QTRY_VERIFY(!(widget.windowState() & Qt::WindowFullScreen));
-#ifdef Q_OS_WIN
-        QEXPECT_FAIL("", "QTBUG-26421", Continue);
-#endif
         QTRY_COMPARE(widget.geometry(), geom);
 
         //Restore to full screen