QDialog Exec occurs QWidget::paintEngine: Should no longer be called

mourad_bilog

Hello everyone,

I've ported my Qt 4.3 application to Qt 5.5 on Mac OS 10.10 using Qt Creator.

When opening a QDialog from an other QDialog, I've the following error

QWidget::paintEngine: Should no longer be called
QPainter::begin: Paint device returned engine == 0, type: 1

I've searched and this error occurs when drawing an image or a QWidget but this is not my case. There's my code to display the dialog :

void frmListeOrdo::addPatient()
{
    frmPatient *w = new frmPatient(this,0,0);

    if(w->exec()) // it craches at this line
    {
        int patient = w->currentPatient();
        if(patient != 0)
        {
            showPatients("");

            QAbstractItemModel* model = tabPatient->model();
            QModelIndex start(model->index(0,0,QModelIndex()));
            QModelIndexList list = model->match(start, Qt::DisplayRole, patient);

            if(!list.isEmpty())
            {
                tabPatient->setCurrentIndex(list[0]);
                tabPatient->scrollTo(model->index(list[0].row(), 1, QModelIndex()));
            }
        }
    }
}

The child dialog constuctor
frmPatient::frmPatient(QWidget *parent, Qt::WindowFlags f, int codePa):QDialog(parent, f), codePatient(codePa)
{
setupUi(this);

// the following lines were commented to ensure that the problem doe's not come from them

//initFiche();   //initialisation des champs de la fiche patient
//initData(codePatient);
//init();
//lnNumDos->setFocus(Qt::MouseFocusReason);
//lbBackColor->setStyleSheet("font-weight:bold;background-color:lightgray");

}

Here's what Qt Creator threads display

0	QPaintEngine::syncState()	QPaintEngine::syncState()		0x100eff919	
1	(anonymous namespace)::QMacCGContext::QMacCGContext(QPainter *)	(anonymous namespace)::QMacCGContext::QMacCGContext(QPainter*)		0x10060e08d	
2	QMacStyle::drawComplexControl(QStyle::ComplexControl, QStyleOptionComplex const *, QPainter *, QWidget const *) const	QMacStyle::drawComplexControl(QStyle::ComplexControl, QStyleOptionComplex const*, QPainter*, QWidget const*) const		0x100620712	
3	QGroupBox::paintEvent(QPaintEvent *)	QGroupBox::paintEvent(QPaintEvent*)		0x1007691bb	
4	QWidget::event(QEvent *)	QWidget::event(QEvent*)		0x1006751bb	
5	QGroupBox::event(QEvent *)	QGroupBox::event(QEvent*)		0x100769495	
6	QApplicationPrivate::notify_helper(QObject *, QEvent *)	QApplicationPrivate::notify_helper(QObject*, QEvent*)		0x1006364bb	
7	QApplication::notify(QObject *, QEvent *)	QApplication::notify(QObject*, QEvent*)		0x10063989e	
8	QCoreApplication::notifyInternal(QObject *, QEvent *)	QCoreApplication::notifyInternal(QObject*, QEvent*)		0x10148a983	
9	QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066e970	
10	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f2ba	
11	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
12	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
13	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
14	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
15	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
16	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice *, QList<QObject *> const&, int, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList<QObject*> const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066f140	
17	QWidgetPrivate::drawWidget(QPaintDevice *, QRegion const&, QPoint const&, int, QPainter *, QWidgetBackingStore *)	QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*)		0x10066ed26	
18	QWidgetBackingStore::doSync()	QWidgetBackingStore::doSync()		0x100642d06	
19	QWidgetBackingStore::sync(QWidget *, QRegion const&)	QWidgetBackingStore::sync(QWidget*, QRegion const&)		0x100641c66

Can anyone tell me where's the problem ?