diff options
Diffstat (limited to 'src/widgets/kernel/qwidget_qpa.cpp')
| -rw-r--r-- | src/widgets/kernel/qwidget_qpa.cpp | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/widgets/kernel/qwidget_qpa.cpp b/src/widgets/kernel/qwidget_qpa.cpp index c524491d22..ef3d7a16d9 100644 --- a/src/widgets/kernel/qwidget_qpa.cpp +++ b/src/widgets/kernel/qwidget_qpa.cpp @@ -980,6 +980,25 @@ void QWidgetPrivate::setWSGeometry(bool dontShow, const QRect &oldRect) QPaintEngine *QWidget::paintEngine() const { qWarning("QWidget::paintEngine: Should no longer be called"); + +#ifdef Q_OS_WIN + // We set this bit which is checked in setAttribute for + // Qt::WA_PaintOnScreen. We do this to allow these two scenarios: + // + // 1. Users accidentally set Qt::WA_PaintOnScreen on X and port to + // Windows which would mean suddenly their widgets stop working. + // + // 2. Users set paint on screen and subclass paintEngine() to + // return 0, in which case we have a "hole" in the backingstore + // allowing use of GDI or DirectX directly. + // + // 1 is WRONG, but to minimize silent failures, we have set this + // bit to ignore the setAttribute call. 2. needs to be + // supported because its our only means of embedding native + // graphics stuff. + const_cast<QWidgetPrivate *>(d_func())->noPaintOnScreen = 1; +#endif + return 0; //##### @@@ } |