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

Discovering QThread


Qt provides a sophisticated threading system. We assume you already know threading basics and the associated issues (deadlocks, threads synchronization, resource sharing, and so on) and we will focus on how Qt implements it.

The QThread is the central class of the Qt threading system. A QThread instance manages one thread of execution within the program.

You can subclass QThread to override the run() function, which will be executed in the QThread framework. Here is how you can create and start a QThread:

QThread thread; 
thread.start(); 

The start() function calling will automatically call the run() function of the thread and emit the started() signal. Only at this point will the new thread of execution be created. When run() is completed, the thread object will emit the finished() signal.

This brings us to a fundamental aspect of QThread: it works seamlessly with the signal/slot mechanism. Qt is an event-driven framework, where a main event loop (or the GUI loop) processes...