paintEvent not getting called with QMainWindow

[yodasoda]

How can you say its called or not. I am in the same situation and I simply put a breakpoint in the function and the program never reached the breakpoint therefor it is not getting called.

[wysota]

You just check if it is called:

#include <QtGui>
 
class MyWindow : public QMainWindow {
public:
  MyWindow(){}
protected:
  void paintEvent(QPaintEvent *pe){
    qDebug() << Q_FUNC_INFO;
    QMainWindow::paintEvent(pe);
  }
};
 
int main(int argc, char **argv){
  QApplication app(argc, argv);
  MyWindow mw;
  mw.show();  
  return app.exec();
}

#include <QtGui>

class MyWindow : public QMainWindow {
public:
  MyWindow(){}
protected:
  void paintEvent(QPaintEvent *pe){
    qDebug() << Q_FUNC_INFO;
    QMainWindow::paintEvent(pe);
  }
};

int main(int argc, char **argv){
  QApplication app(argc, argv);
  MyWindow mw;
  mw.show();  
  return app.exec();
}

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In this example it is called.

[yodasoda]

In my case, this was happening with a QFrame. Here is the solution if anyone ever needs it:

rgbFrame::rgbFrame(QWidget * parent, Qt::WindowFlags f): QFrame(parent, f)
{
    installEventFilter(this);
}
 
void rgbFrame::paintEvent(QPaintEvent *e)
{
    QFrame::paintEvent(e); // pass event to base class
}
 
 
bool rgbFrame::eventFilter(QObject *o, QEvent *e)
{
    if (e->type() == QEvent::Paint) {
        paintEvent((QPaintEvent *)e);
    }
    return QFrame::eventFilter(o, e);
}

rgbFrame::rgbFrame(QWidget * parent, Qt::WindowFlags f): QFrame(parent, f)
{
    installEventFilter(this);
}

void rgbFrame::paintEvent(QPaintEvent *e)
{
    QFrame::paintEvent(e); // pass event to base class
}


bool rgbFrame::eventFilter(QObject *o, QEvent *e)
{
    if (e->type() == QEvent::Paint) {
        paintEvent((QPaintEvent *)e);
    }
    return QFrame::eventFilter(o, e);
}

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