how to get key value

[lzpmail]

hi， i write a simple example, it function to print the key value
this is the code:

bool MainWindow::event(QEvent *event)
{
    if (event->type() == QEvent::KeyPress)
    {
        QKeyEvent *keyEvent = static_cast<QKeyEvent *>(event);
 
        qDebug()<<"kev value "<<keyEvent->key();
    }
 
    return QMainWindow::event(event);
}

bool MainWindow::event(QEvent *event)
{
    if (event->type() == QEvent::KeyPress)
    {
        QKeyEvent *keyEvent = static_cast<QKeyEvent *>(event);

        qDebug()<<"kev value "<<keyEvent->key();
    }

    return QMainWindow::event(event);
}

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but some time can not get some key value, for example end, up, down, page down key value can not print out.

please tell me what why, and have a good example to get key value.
thanks.