TGUI 0.7 is no longer supported, use a newer TGUI version instead.
The connectEx function is provided as an alternative to the optional parameter system so that you can get information from a signal on all compilers. It will removed again in future tgui versions.
The last parameter of your connected function should be an unbound tgui::Callback. Here are two examples:
If you are wondering which members of the Callback class are used for the signal, you should check the documentation of the widget.