Windows QPA: Implement QPlatformWindow::initialize()

Move the code that sends geometry change events from
QWindowsIntegration::createPlatformWindow() to
QWindowsWindow::initialize(), using the obtained geometry
from the creation context. Drop the check for window flags
since they are not changed.

Complements change 4c855a9f9f

Task-number: QTBUG-61977
Change-Id: I0c23abefc45110cc4bf11e10d65dc7ddbb9d20d5
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/plugins/platforms/windows/qwindowscontext.cpp

@@ -405,9 +405,11 @@ QList<int> QWindowsContext::possibleKeys(const QKeyEvent *e) const
     return d->m_keyMapper.possibleKeys(e);
 }
 
-void QWindowsContext::setWindowCreationContext(const QSharedPointer<QWindowCreationContext> &ctx)
+QSharedPointer<QWindowCreationContext> QWindowsContext::setWindowCreationContext(const QSharedPointer<QWindowCreationContext> &ctx)
 {
+    const QSharedPointer<QWindowCreationContext> old = d->m_creationContext;
     d->m_creationContext = ctx;
+    return old;
 }
 
 QSharedPointer<QWindowCreationContext> QWindowsContext::windowCreationContext() const

src/plugins/platforms/windows/qwindowscontext.h

@@ -196,7 +196,7 @@ public:
     QWindow *keyGrabber() const;
     void setKeyGrabber(QWindow *hwnd);
 
-    void setWindowCreationContext(const QSharedPointer<QWindowCreationContext> &ctx);
+    QSharedPointer<QWindowCreationContext> setWindowCreationContext(const QSharedPointer<QWindowCreationContext> &ctx);
     QSharedPointer<QWindowCreationContext> windowCreationContext() const;
 
     void setTabletAbsoluteRange(int a);

src/plugins/platforms/windows/qwindowsintegration.cpp

@@ -344,21 +344,6 @@ QPlatformWindow *QWindowsIntegration::createPlatformWindow(QWindow *window) cons
     if (QWindowsMenuBar *menuBarToBeInstalled = QWindowsMenuBar::menuBarOf(window))
         menuBarToBeInstalled->install(result);
 
-    if (requested.flags != obtained.flags)
-        window->setFlags(obtained.flags);
-    // Trigger geometry change (unless it has a special state in which case setWindowState()
-    // will send the message) and screen change signals of QWindow.
-    if ((obtained.flags & Qt::Desktop) != Qt::Desktop) {
-        const Qt::WindowState state = window->windowState();
-        if (state != Qt::WindowMaximized && state != Qt::WindowFullScreen
-            && requested.geometry != obtained.geometry) {
-            QWindowSystemInterface::handleGeometryChange(window, obtained.geometry);
-        }
-        QPlatformScreen *screen = result->screenForGeometry(obtained.geometry);
-        if (screen && result->screen() != screen)
-            QWindowSystemInterface::handleWindowScreenChanged(window, screen->screen());
-    }
-
     return result;
 }
 

src/plugins/platforms/windows/qwindowswindow.cpp

@@ -76,6 +76,8 @@
 
 QT_BEGIN_NAMESPACE
 
+typedef QSharedPointer<QWindowCreationContext> QWindowCreationContextPtr;
+
 enum {
     defaultWindowWidth = 160,
     defaultWindowHeight = 160
@@ -621,8 +623,6 @@ void WindowCreationData::fromWindow(const QWindow *w, const Qt::WindowFlags flag
 QWindowsWindowData
     WindowCreationData::create(const QWindow *w, const WindowData &data, QString title) const
 {
-    typedef QSharedPointer<QWindowCreationContext> QWindowCreationContextPtr;
-
     WindowData result;
     result.flags = flags;
 
@@ -1070,8 +1070,6 @@ QWindowsWindow::QWindowsWindow(QWindow *aWindow, const QWindowsWindowData &data)
   , m_vkSurface(0)
 #endif
 {
-    // Clear the creation context as the window can be found in QWindowsContext's map.
-    QWindowsContext::instance()->setWindowCreationContext(QSharedPointer<QWindowCreationContext>());
     QWindowsContext::instance()->addWindow(m_data.hwnd, this);
     const Qt::WindowType type = aWindow->type();
     if (type == Qt::Desktop)
@@ -1112,6 +1110,27 @@ QWindowsWindow::~QWindowsWindow()
     destroyIcon();
 }
 
+void QWindowsWindow::initialize()
+{
+    // Clear the creation context as the window can be found in QWindowsContext's map.
+    QWindowCreationContextPtr creationContext =
+        QWindowsContext::instance()->setWindowCreationContext(QWindowCreationContextPtr());
+
+    // Trigger geometry change (unless it has a special state in which case setWindowState()
+    // will send the message) and screen change signals of QWindow.
+    QWindow *w = window();
+    if (w->type() != Qt::Desktop) {
+        const Qt::WindowState state = w->windowState();
+        if (state != Qt::WindowMaximized && state != Qt::WindowFullScreen
+            && creationContext->requestedGeometry != creationContext->obtainedGeometry) {
+            QWindowSystemInterface::handleGeometryChange(w, creationContext->obtainedGeometry);
+        }
+        QPlatformScreen *obtainedScreen = screenForGeometry(creationContext->obtainedGeometry);
+        if (obtainedScreen && screen() != obtainedScreen)
+            QWindowSystemInterface::handleWindowScreenChanged(w, obtainedScreen->screen());
+    }
+}
+
 void QWindowsWindow::fireExpose(const QRegion &region, bool force)
 {
     if (region.isEmpty() && !force)

src/plugins/platforms/windows/qwindowswindow.h

@@ -221,6 +221,8 @@ public:
     QWindowsWindow(QWindow *window, const QWindowsWindowData &data);
     ~QWindowsWindow();
 
+    void initialize() override;
+
     using QPlatformWindow::screenForGeometry;
 
     QSurfaceFormat format() const override { return m_format; }