How to change text format of QDoubleSpinbox?

Question

I want to enter temperature in my dialog in this format 12°15°

For this i took QDoubleSpinBox widget but wasn't able to set its text like above.

I tried following:

degree_sign= u'\N{DEGREE SIGN}'
temperature = QDOubleSpinBox()
temperature.setSuffix(degree_sign)

and got 12.15°

I think valueFromText() and textFromValue() can help but don't know how to use them.

How to set QDoubleSpinBox text(or value) format like 12°15°?

Answer 1

One way is inherit from QDoubleSpinBox and override the respective methods as follows in this pseudo code:

main.cpp

#include <QDoubleSpinBox>
#include <QApplication>

class MySpinBox : public QDoubleSpinBox
{
    Q_OBJECT
    public:
        explicit MySpinBox(QWidget *parent = 0) : QDoubleSpinBox(parent) {}
    double valueFromText(const QString & text) const
    {
        QString valueText = text;
        valueText.chop(1);
        valueText.replace("°", ".");
        return valueText.toFloat();
    }

    QString textFromValue(double value) const
    {
        QString valueText = QString::number(value);
        valueText.replace(".", "°");
        valueText.append(".");
        return valueText;
    }
};

#include "main.moc"

int main(int argc, char **argv)
{
    QApplication application(argc, argv);
    MySpinBox mySpinBox;
    mySpinBox.show();
    return application.exec();
}

main.pro

TEMPLATE = app
TARGET = main
QT += widgets
SOURCES += main.cpp

Build and Run

qmake && make && ./main

Disclaimer: even though it looks like a compiling code, it does not work, but shows the concept.