#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QEvent>
#include <QTextDocument>
#include <QVBoxLayout>
#include <QPixmap>
#include <QIcon>
#include <QBuffer>
#include <QTimer>

class ToolTipButton :
        public QPushButton
{
public:
    ToolTipButton(QWidget *parent=0) :
        QPushButton(parent)
    {

    }

    bool event(QEvent *e)
    {
        if (e->type() == QEvent::ToolTip)
        {
            QTextDocument doc;
            doc.setHtml(toolTip());
            int dtold = 10000 + 40 * qMax(0, toolTip().size() - 100);
            int dtnew = 10000 + 40 * qMax(0, doc.toPlainText().size() - 100);
            qDebug() << "showing tooltip; hide in" << dtold * .001 << "s. Should hide in" << dtnew * .001 << "s";
            QTimer::singleShot(dtold,  [](){qDebug() << "Current Implementation Tooltip closes";});
            QTimer::singleShot(dtnew,  [](){qDebug() << "Wished Implementation Tooltip closes";});

        }
        return QPushButton::event(e);
    }
};


int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget* w = new QWidget();
    QVBoxLayout layout(w);

    ToolTipButton *b1 = new ToolTipButton();
    b1->setToolTip("test");
    ToolTipButton *b2 = new ToolTipButton();
    QPixmap img(64, 64);
    img.fill(Qt::white);
    b2->setIcon(QIcon(img));
    QByteArray ba;
    QBuffer buf;
    buf.setBuffer(&ba);
    img.save(&buf, "PNG");
    b2->setToolTip(QString("test<br><img src=\"data:image/png;base64,%1\">").arg(ba.toBase64()));
    layout.addWidget(b1);
    layout.addWidget(b2);

    w->show();
    return a.exec();
}