problem in QPainter::begin

[xtfllbl]

Did you call the paintEvent, you need that to paint somthing on the widget. If you just write code like paintXXX and not call in the paintEvent, it`ll not work at all.

void MyWidget::paintEvent(QPaintEvent *)
{
 
    QPainter painter(this);
    paintXXXX(QPainter *);

void MyWidget::paintEvent(QPaintEvent *)
{

    QPainter painter(this);
    paintXXXX(QPainter *);

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[wagmare]

=xtfllbl;109807]Did you call the paintEvent, you need that to paint somthing on the widget. If you just write code like paintXXX and not call in the paintEvent, it`ll not work at all.

actually its a bug in Qt ... we cant add a new widget to a widget that is embedded to graphicsView()

see this code

ProxyBug::ProxyBug(QWidget *parent)                                                                                                  : QDialog(parent)
{
        QVBoxLayout *l = new QVBoxLayout( this );
 
        QGraphicsView * group = new QGraphicsView;
        QGraphicsScene * scene = new QGraphicsScene;
        group->setScene(scene);
 
        QGraphicsView * group2 = new QGraphicsView;
        QGraphicsScene * scene2 = new QGraphicsScene;
        group2->setScene(scene2);
 
        group->scene()->addWidget(group2);
        QLineEdit * lineEdit = new QLineEdit;  
        group2->scene()->addWidget(lineEdit);  // this one crashing *
 
        l->addWidget(group);
        setLayout( l );
 
}

ProxyBug::ProxyBug(QWidget *parent)                                                                                                  : QDialog(parent)
{
        QVBoxLayout *l = new QVBoxLayout( this );

        QGraphicsView * group = new QGraphicsView;
        QGraphicsScene * scene = new QGraphicsScene;
        group->setScene(scene);

        QGraphicsView * group2 = new QGraphicsView;
        QGraphicsScene * scene2 = new QGraphicsScene;
        group2->setScene(scene2);

        group->scene()->addWidget(group2);
        QLineEdit * lineEdit = new QLineEdit;  
        group2->scene()->addWidget(lineEdit);  // this one crashing *

        l->addWidget(group);
        setLayout( l );

}

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the group2 is try to embed another widget where group2 itself is embedded by group ...