Adding communication with the observer pattern

In this recipe, we will learn how to implement the observer pattern. The observer pattern provides the ability for a class to register with another class to receive notifications when an event occurs. The Qt language provides this feature through the use of its singles and slots mechanism while requiring a MOC compiler to make it work. This recipe is important as we will learn how to implement the observer pattern without the need for Qt, using standard C++.

Getting ready

Before beginning, please ensure that all of the technical requirements are met, including installing Ubuntu 18.04 or higher and running the following in a Terminal window:

> sudo apt-get install build-essential...