Sometimes, with a QQuickWindow, it can be necessary to handle drop events in C++ for areas that are not covered by a DropArea Qml item. This seems impossible because QQuickWidget::dragEnterEvent always accepts the event, regardless of what its internal QQuickWindow had set as event acceptance. From qquickwidget.cpp:

void QQuickWidget::dragEnterEvent(QDragEnterEvent *e)
{
  Q_D(QQuickWidget);
  d->offscreenWindow->event(e);
  e->accept(); // <-- This line overrides any informative e->setAccepted
               //     that might have been set before.
}

Then if I derive QQuickWidget and overload dragEnterEvent, I cannot know whether I should handle the event or not after having called QQuickWidget::dragEnterEvent, as it always be marked as accepted whether Qml code did accept it or not.