Layout flickers when combobox changes sizehint

The following example shows some suboptimal flickering and even widgets overlapping each other and getting clipped.

#include <QtGui>

class Widget : public QWidget
{
public:
Widget()

{ cbox = new QComboBox; cbox->setSizeAdjustPolicy(QComboBox::AdjustToContents); QLineEdit *spaceEater = new QLineEdit; QHBoxLayout *hbox = new QHBoxLayout; hbox->addWidget(cbox); hbox->addWidget(spaceEater); setLayout(hbox); timerid = startTimer(500); }

protected:
void timerEvent(QTimerEvent *e)
{
if (e->timerId() == timerid)

{ static int count = 0; QString string; string.fill('X', ++count); cbox->addItem(string); }

QWidget::timerEvent(e);
}

private:
int timerid;
QComboBox *cbox;
};

int main(int argc, char **argv)
{
QApplication app(argc, argv);

Widget w;
w.show();

return app.exec();
}