Our second SysInfoWidget is a MemoryWidget class. This widget will display a history of the data so that we can see how the memory consumption evolves over time. To display this data, we will use a QLineSeries class from the Qt Chart module. Create the MemoryWidget class and follow the same pattern we used for CpuWidget:

#include <QtCharts/QLineSeries> 
 
#include "SysInfoWidget.h" 
 
class MemoryWidget : public SysInfoWidget 
{ 
    Q_OBJECT 
public: 
    explicit MemoryWidget(QWidget *parent = 0); 
 
protected slots: 
    void updateSeries() override; 
 
private: 
    QtCharts::QLineSeries* mSeries; 
    qint64 mPointPositionX; 
}; 

Instead of a being QPieSeries*, mSeries is a type of QLineSeries* that will be linked to the chart object in a very similar fashion to MemoryWidget.cpp:

#include "MemoryWidget.h" 
#include <QtCharts...