ActiveQt : Setting Currency properties of a QAxObject

**drfitz** · 25th July 2012, 10:06

I'm accessing some third-party COM objects that have Currency/Decimal properties. ActiveQt supports the Currency (CY) type of COM, which is simply an int64, using qlonglong. For instance, an amount of $1.23 is saved as 12300. Reading such a currency property in a QAxObject is not a problem -- I simply divide by 10000 to get the real amount. However, setting such a property is a problem since the input is taken "at face value". Floating point numbers are converted to qlonglongs and cents are omitted in the conversion:

Qt Code:

Switch view

double value1 = 1.23;
qaxobject->setProperty("Amount", value1);
// property("Amount") returns 10000 = $1
 
// Multiplying by 10,000 beforehand therefore doesn't work either
qlonglong value2 = 12300; // trying again for $1.23
qaxobject->setProperty("Amount", value2);
// property("Amount") returns 123000000 = $12300

double value1 = 1.23;
qaxobject->setProperty("Amount", value1);
// property("Amount") returns 10000 = $1

// Multiplying by 10,000 beforehand therefore doesn't work either
qlonglong value2 = 12300; // trying again for $1.23
qaxobject->setProperty("Amount", value2);
// property("Amount") returns 123000000 = $12300

To copy to clipboard, switch view to plain text mode

Is this because of the conversion to QVariant? If so, does anybody know a way around setProperty/dynamicCall to set the property in its native type? Or are the third-party components at fault? Thanks a lot.
(Using Qt4.8.2, Visual Studio 2010)