Add accessors for QWindow and QScreen to QWidgetPrivate

Rewrite the existing accessor QWidgetPrivate::windowHandle() to
accept a mode enumeration that has an "Any" convenience.

Based on that, add QWidgetPrivate::associatedScreen(), which is seful
in many places where scaling is performed.

Prototypically simplify the code.

Task-number: QTBUG-62094
Task-number: QTBUG-73231
Change-Id: I516288363d329bce9bc94e4951106f9357bc6cde
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
 
 
 

5 files changed, 43 insertions, 29 deletions

diff --git a/src/widgets/kernel/qdesktopwidget.cpp b/src/widgets/kernel/qdesktopwidget.cpp
index d17c7eb36c..ac0cfcf2f5 100644
--- a/src/widgets/kernel/qdesktopwidget.cpp
+++ b/src/widgets/kernel/qdesktopwidget.cpp
@@ -321,20 +321,12 @@ int QDesktopWidgetPrivate::screenNumber(const QWidget *w)
     if (screens.isEmpty()) // This should never happen
         return primaryScreen();
 
-    const QWindow *winHandle = w->windowHandle();
-    if (!winHandle) {
-        if (const QWidget *nativeParent = w->nativeParentWidget())
-            winHandle = nativeParent->windowHandle();
-    }
-
     // If there is more than one virtual desktop
     if (screens.count() != screens.constFirst()->virtualSiblings().count()) {
         // Find the root widget, get a QScreen from it and use the
         // virtual siblings for checking the window position.
-        if (winHandle) {
-            if (const QScreen *winScreen = winHandle->screen())
-                screens = winScreen->virtualSiblings();
-        }
+        if (const QScreen *winScreen = qt_widget_private(const_cast<QWidget *>(w))->associatedScreen())
+            screens = winScreen->virtualSiblings();
     }
 
     // Get the screen number from window position using screen geometry
diff --git a/src/widgets/kernel/qopenglwidget.cpp b/src/widgets/kernel/qopenglwidget.cpp
index 374ea53726..ae7729b49b 100644
--- a/src/widgets/kernel/qopenglwidget.cpp
+++ b/src/widgets/kernel/qopenglwidget.cpp
@@ -1333,11 +1333,8 @@ int QOpenGLWidget::metric(QPaintDevice::PaintDeviceMetric metric) const
     if (d->inBackingStorePaint)
         return QWidget::metric(metric);
 
-    QWidget *tlw = window();
-    QWindow *window = tlw ? tlw->windowHandle() : 0;
-    QScreen *screen = tlw && tlw->windowHandle() ? tlw->windowHandle()->screen() : 0;
-    if (!screen && QGuiApplication::primaryScreen())
-        screen = QGuiApplication::primaryScreen();
+    auto window = d->windowHandle(QWidgetPrivate::WindowHandleMode::TopLevel);
+    QScreen *screen = window ? window->screen() : QGuiApplication::primaryScreen();
 
     const float dpmx = qt_defaultDpiX() * 100. / 2.54;
     const float dpmy = qt_defaultDpiY() * 100. / 2.54;
diff --git a/src/widgets/kernel/qwidget.cpp b/src/widgets/kernel/qwidget.cpp
index 58963d5eec..be2906a743 100644
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@@ -1252,6 +1252,33 @@ void QWidgetPrivate::createRecursively()
     }
 }
 
+QWindow *QWidgetPrivate::windowHandle(WindowHandleMode mode) const
+{
+    if (mode == WindowHandleMode::Direct || mode == WindowHandleMode::Closest) {
+        if (QTLWExtra *x = maybeTopData())
+            return x->window;
+    }
+    if (mode == WindowHandleMode::Closest) {
+        if (auto nativeParent = q_func()->nativeParentWidget()) {
+            if (auto window = nativeParent->windowHandle())
+                return window;
+        }
+    }
+    if (mode == WindowHandleMode::TopLevel || mode == WindowHandleMode::Closest) {
+        if (auto topLevel = q_func()->topLevelWidget()) {
+            if (auto window = topLevel ->windowHandle())
+                return window;
+        }
+    }
+    return nullptr;
+}
+
+QScreen *QWidgetPrivate::associatedScreen() const
+{
+    if (auto window = windowHandle(WindowHandleMode::Closest))
+        return window->screen();
+    return nullptr;
+}
 
 // ### fixme: Qt 6: Remove parameter window from QWidget::create()
 
@@ -8103,7 +8130,7 @@ void QWidgetPrivate::show_sys()
 {
     Q_Q(QWidget);
 
-    QWidgetWindow *window = windowHandle();
+    auto window = qobject_cast<QWidgetWindow *>(windowHandle());
 
     if (q->testAttribute(Qt::WA_DontShowOnScreen)) {
         invalidateBackingStore(q->rect());
@@ -8242,7 +8269,7 @@ void QWidgetPrivate::hide_sys()
 {
     Q_Q(QWidget);
 
-    QWidgetWindow *window = windowHandle();
+    auto window = qobject_cast<QWidgetWindow *>(windowHandle());
 
     if (q->testAttribute(Qt::WA_DontShowOnScreen)) {
         q->setAttribute(Qt::WA_Mapped, false);
diff --git a/src/widgets/kernel/qwidget_p.h b/src/widgets/kernel/qwidget_p.h
index c073b8fb03..1f36c192f5 100644
--- a/src/widgets/kernel/qwidget_p.h
+++ b/src/widgets/kernel/qwidget_p.h
@@ -342,7 +342,15 @@ public:
     QPainter *sharedPainter() const;
     void setSharedPainter(QPainter *painter);
     QWidgetBackingStore *maybeBackingStore() const;
-    QWidgetWindow *windowHandle() const;
+
+    enum class WindowHandleMode {
+        Direct,
+        Closest,
+        TopLevel
+    };
+    QWindow *windowHandle(WindowHandleMode mode = WindowHandleMode::Direct) const;
+
+    QScreen *associatedScreen() const;
 
     template <typename T>
     void repaint(T t);
@@ -1014,13 +1022,6 @@ inline QWidgetBackingStore *QWidgetPrivate::maybeBackingStore() const
     return x ? x->backingStoreTracker.data() : nullptr;
 }
 
-inline QWidgetWindow *QWidgetPrivate::windowHandle() const
-{
-    if (QTLWExtra *x = maybeTopData())
-        return x->window;
-    return nullptr;
-}
-
 QT_END_NAMESPACE
 
 #endif // QWIDGET_P_H
diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index 70b305326c..a5d9eee49d 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -592,10 +592,7 @@ void QWidgetWindow::handleMouseEvent(QMouseEvent *event)
                         w->window()->raise();
                     }
 
-                    QWindow *win = w->windowHandle();
-                    if (!win)
-                        win = w->nativeParentWidget()->windowHandle();
-                    if (win) {
+                    if (auto win = qt_widget_private(w)->windowHandle(QWidgetPrivate::WindowHandleMode::Closest)) {
                         const QRect globalGeometry = win->isTopLevel()
                             ? win->geometry()
                             : QRect(win->mapToGlobal(QPoint(0, 0)), win->size());