Fixed tst_qwidget::testContentsPropagation auto-test failure.

Some auto-tests render into a QPixmap and check the result against
QPixmap::grabWidget(). Change acc1a2bd5520369c made grabWidget() render
into a QImage to be able to preserve background transparency. Instead,
to avoid breaking various auto-tests, we can use a QPixmap and fill it
with transparent if the widget's isOpaque flag is not set.

Task-number: QTBUG-14945
Reviewed-by: Kim

1 files changed, 5 insertions, 3 deletions

diff --git a/src/gui/image/qpixmap.cpp b/src/gui/image/qpixmap.cpp
index 290c0f0..c5d9a7e 100644
--- a/src/gui/image/qpixmap.cpp
+++ b/src/gui/image/qpixmap.cpp
@@ -1101,11 +1101,13 @@ QPixmap QPixmap::grabWidget(QWidget * widget, const QRect &rect)
     if (!r.intersects(widget->rect()))
         return QPixmap();
 
-    QImage res(r.size(), QImage::Format_ARGB32_Premultiplied);
-    res.fill(0);
+    QPixmap res(r.size());
+    if (!qt_widget_private(widget)->isOpaque)
+        res.fill(Qt::transparent);
+
     widget->d_func()->render(&res, QPoint(), r, QWidget::DrawWindowBackground
                              | QWidget::DrawChildren | QWidget::IgnoreMask, true);
-    return QPixmap::fromImage(res);
+    return res;
 }
 
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