Game Programming Using Qt

Time for action – writing the OOP conform code using QSignalMapper

A more elegant way that does not rely on sender() would be to use QSignalMapper and a local hash, in which all replies that are connected to that slot are stored. So, whenever you call QNetworkAccessManager::get(), store the returned pointer in a member variable of the QHash<int, QNetworkReply*> type and set up the mapper. Let's assume that we have the following member variables and that they are set up properly:

QNetworkAccessManager *m_nam;
QSignalMapper *m_mapper;
QHash<int, QNetworkReply*> m_replies;

Then, you connect the finished() signal of a reply this way:

QNetworkReply *reply = m_nam->get(QNetworkRequest(QUrl(/*...*/))); connect(reply, SIGNAL(finished()), m_mapper, SLOT(map())); ...