// 文件名: NoFocusRectStyle.h
#ifndef NOFOCUSRECTSTYLE_H
#define NOFOCUSRECTSTYLE_H
#include <QProxyStyle>
class NoFocusRectStyle : public QProxyStyle
{
public:
    NoFocusRectStyle(QStyle *baseStyle) : QProxyStyle(baseStyle) {}
    void drawPrimitive(PrimitiveElement element,
                       const QStyleOption *option,
                       QPainter *painter,
                       const QWidget *widget = 0) const
{
        if (element == QStyle::PE_FrameFocusRect)
        {
            return;
        }
        QProxyStyle::drawPrimitive(element, option, painter, widget);
    }
};
#endif // NOFOCUSRECTSTYLE_H

// 文件名: main.cpp
#include "Widget.h"
#include "NoFocusRectStyle.h"
#include <QApplication>
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    NoFocusRectStyle *style = new NoFocusRectStyle(app.style());
    app.setStyle(style); // Ownership of the style object is transferred to QApplication
    Widget w;
    w.show();
    return app.exec();
}