QAssociativeIterable Class

Detailed Description

This class allows several methods of accessing the elements of an associative container held within a QVariant. An instance of QAssociativeIterable can be extracted from a QVariant if it can be converted to a QVariantHash or QVariantMap.

 QHash<int, QString> mapping;
 mapping.insert(7, "Seven");
 mapping.insert(11, "Eleven");
 mapping.insert(42, "Forty-two");

 QVariant variant = QVariant::fromValue(mapping);
 if (variant.canConvert<QVariantHash>()) {
     QAssociativeIterable iterable = variant.value<QAssociativeIterable>();
     // Can use foreach over the values:
     foreach (const QVariant &v, iterable) {
         qDebug() << v;
     }
     // Can use C++11 range-for over the values:
     for (const QVariant &v : iterable) {
         qDebug() << v;
     }
     // Can use iterators:
     QAssociativeIterable::const_iterator it = iterable.begin();
     const QAssociativeIterable::const_iterator end = iterable.end();
     for ( ; it != end; ++it) {
         qDebug() << *it; // The current value
         qDebug() << it.key();
         qDebug() << it.value();
     }
 }

The container itself is not copied before iterating over it.