Any QWidget with a focus proxy inside a QGraphicsProxyWidget will fire QEvent::FocusIn on every mouse click

#include <QtGui>

class test : public QDoubleSpinBox
{
	bool event( QEvent * event )
	{
		switch (event->type())
		{
			case QEvent::FocusIn:
			{
				setValue( value() + 1 );
			}
			break;
			case QEvent::FocusOut:
			{
				setValue( value() - 1 );
			}
			break;
		}
		return QDoubleSpinBox::event( event );
	}
};

int main(int argc, char **argv)
{
	QApplication app( argc, argv );
	test edit;
	QGraphicsScene *dummyScene = new QGraphicsScene();
	dummyScene->addWidget( &edit );
	QGraphicsView *view = new QGraphicsView( dummyScene );

	view->show();
	return qApp->exec();
}

void QWidget::setFocus(Qt::FocusReason reason)
{
    if (!isEnabled())
        return;

    QWidget *f = this;
    while (f->d_func()->extra && f->d_func()->extra->focus_proxy)
        f = f->d_func()->extra->focus_proxy;

    if (QApplication::focusWidget() == f
#if defined(Q_DEAD_CODE_FROM_QT4_WIN)
        && GetFocus() == f->internalWinId()
#endif
       )
        return;

#ifndef QT_NO_GRAPHICSVIEW
    QWidget *previousProxyFocus = 0;
    if (QWExtra *topData = window()->d_func()->extra) {
        if (topData->proxyWidget && topData->proxyWidget->hasFocus()) {
            previousProxyFocus = topData->proxyWidget->widget()->focusWidget();
            if (previousProxyFocus && previousProxyFocus->focusProxy())
                previousProxyFocus = previousProxyFocus->focusProxy();
            if (previousProxyFocus == this && !topData->proxyWidget->d_func()->proxyIsGivingFocus)
                return;
        }
    }
#endif
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