很奇怪，似乎painter不工作，请帮忙解决问题 [复制链接]

QString title = tr("检测结果");
    QPrinter    printer(QPrinter::HighResolution);
    QPrintDialog  printDialog(&printer, this);

    if (printDialog.exec()==QDialog::Accepted)
    {
         QPainter painter(&printer);
        qDebug()<<"hello world!"<<endl;
        painter.drawText(200,400,title);
        qDebug()<<"hello world2222"<<endl;
}

调试输出正常 输出信息； painter.drawText(200,400,title) 却始终无法在纸上打印出来:检测结果

Warning: When the paintdevice is a widget, QPainter can only be used inside a paintEvent() function or in a function called by paintEvent();