How to get qInfo() as a QString?

Question

I'm trying to access the coordinates of a MapQuickItem in QML from C++. The latitude has 9 decimal digits and longitude has 8 decimal digits. But if I try to access them using latitude(), I lose the last 5 decimal places. If I try to use toString(QGeoCoordinate::Degrees), I only get 5 decimal digits. But when I print out the QGeoCoordinate directly using qInfo(), it shows all 9 digits.

Is there a way to grab the qInfo() output and store them inside a QString, or otherwise get the full decimal places of the latitude and longitude?

C++:

QObject *pin = qvariant_cast<QObject *>(mapObject -> property("destination"));
QGeoCoordinate dest = qvariant_cast<QGeoCoordinate>(pin->property("coordinate"));
qInfo() << "dest: " << dest;
qInfo() << dest.toString(QGeoCoordinate::Degrees);
qInfo() << dest.latitude();
qInfo() << dest.longitude();

Output:

dest:  QGeoCoordinate(33.751513868, -118.1781581, 0)
"33.75151°, -118.17816°, 0m"
33.7515
-118.178

Answer 1

You can either use qSetRealNumberPrecision or QString::number.

double d = 123456789.987654321;
qInfo() << qSetRealNumberPrecision(15) << d;
qInfo() << QString::number(d, 'f', 6);

Output

123456789.987654
"123456789.987654"

---

QGeoCoordinate coordinate(33.751513868, -118.1781581, 0);

qInfo() << coordinate;
qInfo() << qSetRealNumberPrecision(11) << coordinate.latitude()
                                       << coordinate.longitude();
qInfo() << QString::number(coordinate.latitude(), 'f', 9)
        << QString::number(coordinate.longitude(), 'f', 9);

Output

QGeoCoordinate(33.751513868, -118.1781581, 0)
33.751513868 -118.1781581
"33.751513868" "-118.178158100"