Let's buckle up and do this project! Create a new Qt Widgets Application project named ch11-drum-machine. As usual, add the CONFIG += c++14 in ch11-drum-machine.pro.

Now create a new C++ class named SoundEvent. Here is SoundEvent.h stripped from its functions:

#include <QtGlobal> 
 
class SoundEvent 
{ 
 
public: 
    SoundEvent(qint64 timestamp = 0, int soundId = 0); 
    ~SoundEvent(); 
 
    qint64 timestamp; 
    int soundId; 
}; 

This class contains only two public members:

In recording mode, each time the user plays a sound, a SoundEvent is created with the appropriate data. The SoundEvent.cpp file is so boring that we will not inflict it on you.

The next class to build is Track. Again, create the new C++ class. Let's review Track.h with its members only:

#include <QObject&gt...