qSort with lessThan

[soul_rebel]

Hi everyone!

I want to do custom sorting with a QList (its a list of pointers so the sorting has to be custom...)

I followed the doc and wrote:

bool QBsdPortGlobal::lessThan(QBsdPort* p1, QBsdPort* p2);
{
    return p1->origin() < p2->origin();
}

bool QBsdPortGlobal::lessThan(QBsdPort* p1, QBsdPort* p2);
{
    return p1->origin() < p2->origin();
}

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but whenver I call

qSort(m_collection.begin(),
              m_collection.end(),
              lessThan);

qSort(m_collection.begin(),
              m_collection.end(),
              lessThan);

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I get:

bsdportglobal.cpp:497: error: no matching function for call to 'qSort(QList<QBsdPort*>::iterator, QList<QBsdPort*>::iterator, <unresolved overloaded function type>)'             
/usr/local/include/qt4/QtCore/qalgorithms.h:203: note: candidates are: void qSort(RandomAccessIterator, RandomAccessIterator, LessThan) [with RandomAccessIterator = QList<QBsdPort*>::iterator, LessThan = bool (QBsdPortGlobal::*)(QBsdPort*, QBsdPort*)]

bsdportglobal.cpp:497: error: no matching function for call to 'qSort(QList<QBsdPort*>::iterator, QList<QBsdPort*>::iterator, <unresolved overloaded function type>)'             
/usr/local/include/qt4/QtCore/qalgorithms.h:203: note: candidates are: void qSort(RandomAccessIterator, RandomAccessIterator, LessThan) [with RandomAccessIterator = QList<QBsdPort*>::iterator, LessThan = bool (QBsdPortGlobal::*)(QBsdPort*, QBsdPort*)]

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Why is lessThan() unresovled? I put it in the source and it is declared in the header. The fcuntion works otherwise...

Thanks for your help!

[aamer4yu]

Where are you calling the function qSort from ?
lessThan seems to be a member function of QBsdPortGlobal. So if are calling qSort outside the class, u must be getting error.
Hope am not wrong

[soul_rebel]

Thanks for the reply.

I only call qSort from other member-functions of QBsdPort::global...

[caduel]

You can not use a member function (needs an object to be called upon).

You can:
* make your function static
* make a plain function (outside of a class)
* make a regular function object
* use something like Boost.Bind

HTH

[soul_rebel]

Thanks, I made it static.