qss中，怎么表达代码里的button->setFocusPolicy(Qt:NoFocus)

QPushButton
{
    color : red;
    policy : nofocus; /*如何表达无焦点？*/
}

#include <QtGui/QApplication>
#include "mainwindow.h"

//the following three header files are used for suppporting setSkin function
#include <QFile>
#include <QStyleFactory>
#include <QTextStream>

bool setSkin(QApplication* const app, QString const &skinFile);

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    //load qss file for skin
    setSkin(&a ,"skin.qss");

    return a.exec();
}

bool setSkin(QApplication* const app, QString const &skinFile)
{
    QFile file(skinFile);

    if (QFile::exists(skinFile) && file.open(QIODevice::ReadOnly))
    {
        QApplication::setStyle(QStyleFactory::create("Windows"));
        QString strTemp;
        QTextStream in(&file);
        while (!in.atEnd())
        {
            strTemp.append(in.readLine());
        }
        file.close();
        app->setStyleSheet(strTemp);
    }
    else
    {
#ifdef Q_WS_MAC
        qDebug("%s: %s: File does not exist %s... setting mac style...",
               __FILE__, __FUNCTION__, qPrintable(skinFile));
        app->setStyle(new QMacStyle());
        return true;
#else
        qDebug("%s: %s: File does not exist or failed to open %s",
               __FILE__, __FUNCTION__, qPrintable(skinFile));
        return false;
#endif
    }

    return true;
}