Resolve QWidget window handle without depending on QtWidgets

Change-Id: If5b2f17283193d7a1718f476b72f380e9e67d0f0
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 10 insertions, 15 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoadrag.mm b/src/plugins/platforms/cocoa/qcocoadrag.mm
index b4a16ab912..3525fddfd1 100644
--- a/src/plugins/platforms/cocoa/qcocoadrag.mm
+++ b/src/plugins/platforms/cocoa/qcocoadrag.mm
@@ -40,9 +40,6 @@
 #include "qcocoadrag.h"
 #include "qmacclipboard.h"
 #include "qcocoahelpers.h"
-#ifndef QT_NO_WIDGETS
-#include <QtWidgets/qwidget.h>
-#endif
 #include <QtGui/private/qcoregraphics_p.h>
 
 QT_BEGIN_NAMESPACE
@@ -189,19 +186,17 @@ QPixmap QCocoaDrag::dragPixmap(QDrag *drag, QPoint &hotSpot) const
                 const int height = fm.height();
                 if (width > 0 && height > 0) {
                     qreal dpr = 1.0;
-                    if (const QWindow *sourceWindow = qobject_cast<QWindow *>(drag->source())) {
-                        dpr = sourceWindow->devicePixelRatio();
-                    }
-#ifndef QT_NO_WIDGETS
-                    else if (const QWidget *sourceWidget = qobject_cast<QWidget *>(drag->source())) {
-                        if (const QWindow *sourceWindow = sourceWidget->window()->windowHandle())
-                            dpr = sourceWindow->devicePixelRatio();
-                    }
-#endif
-                    else {
-                        if (const QWindow *focusWindow = qApp->focusWindow())
-                            dpr = focusWindow->devicePixelRatio();
+                    QWindow *window = qobject_cast<QWindow *>(drag->source());
+                    if (!window && drag->source()->metaObject()->indexOfMethod("_q_closestWindowHandle()") != -1) {
+                        QMetaObject::invokeMethod(drag->source(), "_q_closestWindowHandle",
+                            Q_RETURN_ARG(QWindow *, window));
                     }
+                    if (!window)
+                        window = qApp->focusWindow();
+
+                    if (window)
+                        dpr = window->devicePixelRatio();
+
                     pm = QPixmap(width * dpr, height * dpr);
                     pm.setDevicePixelRatio(dpr);
                     QPainter p(&pm);