Book Image

Hands-On High Performance Programming with Qt 5

By : Marek Krajewski
5 (1)
Book Image

Hands-On High Performance Programming with Qt 5

5 (1)
By: Marek Krajewski

Overview of this book

Achieving efficient code through performance tuning is one of the key challenges faced by many programmers. This book looks at Qt programming from a performance perspective. You'll explore the performance problems encountered when using the Qt framework and means and ways to resolve them and optimize performance. The book highlights performance improvements and new features released in Qt 5.9, Qt 5.11, and 5.12 (LTE). You'll master general computer performance best practices and tools, which can help you identify the reasons behind low performance, and the most common performance pitfalls experienced when using the Qt framework. In the following chapters, you’ll explore multithreading and asynchronous programming with C++ and Qt and learn the importance and efficient use of data structures. You'll also get the opportunity to work through techniques such as memory management and design guidelines, which are essential to improve application performance. Comprehensive sections that cover all these concepts will prepare you for gaining hands-on experience of some of Qt's most exciting application fields - the mobile and embedded development domains. By the end of this book, you'll be ready to build Qt applications that are more efficient, concurrent, and performance-oriented in nature
Table of Contents (14 chapters)

Threads, events, and QObjects

If it wasn't for the QObject, we could probably just use the C++ standard thread class. However, a QObject can emit and receive signals and Qt offers infrastructure to do so in a multithread-safe (MT-safe) way. In order to be able to understand this mechanism, we have first to take a look at signals, slots, and asynchronous processing in Qt.

Events and event loop

Qt is an event-driven toolkit and this means that we are always reacting to some events occurring in the system. Thus, we are doing all things asynchronously—we will be notified of something, then we react to it in some specific callback, and then we are done. So, our program isn't one single code strand, it's rather...