Add Http Proxy support to existing application using QNetworkProxy

Introduction

Suppose you have an existing Qt application that makes use of QtNetwork classes. Qt let you specify a proxy for every connection you create, but there is simple way to set global proxy settings so the whole application will use those settings for any connection it will use.

Idea and implementation

You just need to insert this sample code in your main.cpp (please insert it right before return a.exec();) in the main(...) method. Of course in this way the proxy settings will be hardcoded, but you can always read/save them from a configuration file, using the QSettings class.

QNetworkProxy proxy;
proxy.setType(QNetworkProxy::HttpProxy);
proxy.setHostName("proxy.example.com");
proxy.setPort(1080);
proxy.setUser("username");
proxy.setPassword("password");
QNetworkProxy::setApplicationProxy(proxy);