Game Programming Using Qt Beginner's Guide

Time for action – downloading a file

First, create an instance of QNetworkAccessManager:

QNetworkAccessManager *m_nam = new QNetworkAccessManager(this);

Since QNetworkAccessManager inherits QObject, it takes a pointer to QObject, which is used as a parent. Thus, you do not have to take care of deleting the manager later on. Furthermore, one single instance of QNetworkAccessManager is enough for an entire application. So, either pass a pointer to the network access manager in your game or, for ease of use, create a singleton pattern and access the manager through that.

Tip

A singleton pattern ensures that a class is instantiated only once. The pattern is useful for accessing application-wide configurations or—as in our case—an instance of QNetworkAccessManager ...