This is my template
template <class T>
void writeData(QVector<T> &vec, const QString &fp, void(T::*method_ptr)(QFile&) )
{
QFile f(fp);
if(!f.open(QIODevice::WriteOnly | QIODevice::Append) )
{
qDebug() << "File error" << f.error();
}
else
{
QThread::currentThread();
for(T &tw : vec)
{
(tw.*method_ptr)(f);
}
}
f.close();
}
And here I would use my template:
//teams is like: QVector<teamType> teams
QFuture<void> fut = run(writeData, teams, filePath, &teamType::writeTeams); // no matching function for call 'run'
~~~ ~~~~~~~~~~~~~~~~~~~
//So, what´s wrong here?
Because this works fine:
writeData(teams, filePath, &teamType::writeTeams);
And "&teamType::writeTeams" cames from the following:
void teamType::writeTeams(QFile &f)
{
QTextStream out(&f);
out.setCodec("UTF-16LE");
out << teamId << "\t" << offsideTrap << "\t" << withoutBall << "\t" << formationId << "\t"
<< attack << "\t" << teamMentality << "\t" << attackTactic1 << "\t"
<< attackTactic2 << "\t" << defenseTactic1 << "\t" << defenseTactic2 << "\t" << captain << "\t"
<< penaltyTakerId << "\t" << kickTakerId << "\t" << leftCornerkickTakerId << "\t" << rightCornerkickTakerId << "\t"
<< numTransfersIn << endl;
}
It´s a member function in class "teamType"
because writeData
is a function template there is no mechanism that run
can use to get the correct instantiation of that template for the parameters.
A real easy fix for this is to just wrap the call in a lambda. That would look like
QFuture<void> fut = run([=](){ writeData(teams, filePath, &teamType::writeTeams); });
and now that the call to writeData
is actually done with the function parameters, template argument deduction will succeed and the code will compile.