Use of colon after class name in c++

Question

This is a header file extracted from a blackberry 10 helloworld program.

#ifndef ApplicationUI_HPP_
#define ApplicationUI_HPP_

#include 

na         


        

Answer 1

It means that ApplicationUI inherits all methods and member variables from the class QObject. The use of public means that the public methods and members of QObject are also public in ApplicationUI.