Window overlay

class DiagnosticStyle : public QWindowsVistaStyle
{
Q_OBJECT

public:
    typedef QWindowsVistaStyle BaseStyle;
    void drawControl(ControlElement element, const QStyleOption* option, QPainter* painter, const QWidget* widget) const;
};


void DiagnosticStyle::drawControl(ControlElement element, const QStyleOption* option, QPainter* painter, const QWidget* widget) const
{
    BaseStyle::drawControl(element, option, painter, widget);
    if (widget && painter) {
        // draw a border around the widget
        painter->setPen(QColor("red"));
        painter->drawRect(widget->rect());

        // show the classname of the widget
        QBrush translucentBrush(QColor(255,246,240, 100));
        painter->fillRect(widget->rect(), translucentBrush);
        painter->setPen(QColor("darkblue"));
        painter->drawText(widget->rect(), Qt::AlignLeft | Qt::AlignVCenter, widget->metaObject()->className());
    }
}

qApp->setStyle(new DiagnosticStyle());
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