QMap swap key and value

[Vadi2]

I've got this bit of code which basically reverses the key and value in a QMap:

        QMap<QString, int> modulePri = host->mModulePriorities;
        QMapIterator<QString, int> modulePriosIterator(modulePri);
        QMap<int, QStringList> moduleOrder;
        while (modulePriosIterator.hasNext()) {
            modulePriosIterator.next();
            // setup the map to be in format of priority:name
            moduleOrder[modulePriosIterator.value()].append(modulePriosIterator.key());
        }
        QMapIterator<int, QStringList> it4(moduleOrder);
        while (it4.hasNext()) {
            it4.next();
            QStringList moduleList = it4.value();
            for (int i = 0; i < moduleList.size(); i++) {
                QString moduleName = moduleList[i];
                if (mModulesToSync.contains(moduleName)) {
                    host->reloadModule(moduleName);
                }
            }
        }

Is there a way to write it shorter in Qt 5.7 + C++14?

[SGaist]

Hi,

QMap<QString, int> modulePri;
modulePri["one"] = 1;
modulePri["two"] = 2;
QMap<int, QStringList> moduleOrder;

// Qt 5.7
for (auto it = modulePri.keyBegin() ; it != modulePri.keyEnd() ; ++it) {
    moduleOrder[modulePri[*it]].append(*it);
}

// Qt 5.10
for (auto it = modulePri.constKeyValueBegin() ; it != modulePri.constKeyValueEnd() ; ++it) {
    moduleOrder[(*it).second].append((*it).first);
}

[Vadi2]

Thanks a ton!