Book Image

Mastering Qt 5

By : Guillaume Lazar, Robin Penea
Book Image

Mastering Qt 5

By: Guillaume Lazar, Robin Penea

Overview of this book

Qt 5.7 is an application development framework that provides a great user experience and develops full-capability applications with Qt Widgets, QML, and even Qt 3D. This book will address challenges in successfully developing cross-platform applications with the Qt framework. Cross-platform development needs a well-organized project. Using this book, you will have a better understanding of the Qt framework and the tools to resolve serious issues such as linking, debugging, and multithreading. Your journey will start with the new Qt 5 features. Then you will explore different platforms and learn to tame them. Every chapter along the way is a logical step that you must take to master Qt. The journey will end in an application that has been tested and is ready to be shipped.
Table of Contents (20 chapters)
Mastering Qt 5
Credits
About the Authors
About the Reviewer
www.PacktPub.com
Preface

Memory using Qcharts


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

#include "MemoryWidget.h" 
#include <QtCharts/QAreaSeries> 
 
using namespace QtCharts; 
 
const int CHART_X_RANGE_COUNT = 50; 
const int CHART_X_RANGE_MAX = CHART_X_RANGE_COUNT...