QVariant streaming from QDataStream

[XCG]

Hi
I'm using Qt 4.3.3 and trying to stream binary data (read from an arbitrary file). Therefore I started with an example as found in the Qt documentation just a few lines of code:

#include <QVariant>
#include <QDataStream>
#include <QString>
#include <QStringList>
#include <QFile>
 
 
int main(int argc, char *argv[])
{
    QFile file("./test");
    file.open(QIODevice::ReadOnly);
 
    QVariant v(123);                              // The variant now contains
    int x = v.toInt();                              // x = 123
 
    qDebug("x=%#x", x);                      // prints x
 
    QDataStream in(&file);                      
 
                                                          // prints "Type is int"
    qDebug("Type is %s, userType=%d", v.typeName(), v.userType());
 
    in >> v;                                         // *Should* reads an Int variant
 
    int z = v.toInt();                              // z = 0 !!!!
                                                         // Type is no longer Int variant:
    qDebug("Type is %s, userType=%d", v.typeName(), v.userType());
 
    int n;
    in >> n;                                         // Reads a normal int
 
    qDebug("n=%#x", n);                      // this just works 
 
    return 1;
}

#include <QVariant>
#include <QDataStream>
#include <QString>
#include <QStringList>
#include <QFile>


int main(int argc, char *argv[])
{
    QFile file("./test");
    file.open(QIODevice::ReadOnly);

    QVariant v(123);                              // The variant now contains
    int x = v.toInt();                              // x = 123

    qDebug("x=%#x", x);                      // prints x

    QDataStream in(&file);                      

                                                          // prints "Type is int"
    qDebug("Type is %s, userType=%d", v.typeName(), v.userType());

    in >> v;                                         // *Should* reads an Int variant

    int z = v.toInt();                              // z = 0 !!!!
                                                         // Type is no longer Int variant:
    qDebug("Type is %s, userType=%d", v.typeName(), v.userType());

    int n;
    in >> n;                                         // Reads a normal int

    qDebug("n=%#x", n);                      // this just works 

    return 1;
}

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Here the few lines produce the following output:

markus@athlon:~/Test/bin> ./test
x=0x7b
Type is int, userType=2
QVariant::load: unable to load type 1061506118.
Type is (null), userType=1061506118
n=0x1010000
markus@athlon:~/Test/bin>

So it looks like the QVariant type is lost somehow during the call to the operator>>. Does anybody have an idea why the type has suddenly the value 1061506118 instead of 2?


Best regards, Markus