Preface

With the growing need to develop GUIs for multiple targets and screens, improving the visual quality of your application becomes important so that it stands out from your competitors. With its cross-platform ability and the latest UI paradigms, Qt makes it possible to build intuitive, interactive, and user-friendly user interfaces for your applications.

Qt 6 C++ GUI Programming Cookbook, Third Edition, teaches you how to develop functional and appealing user interfaces using the latest version of QT6 and C++. This book will help you learn a variety of topics such as GUI customization and animation, graphics rendering, and implementing Google Maps. You will also explore advanced concepts such as asynchronous programming, event handling using signals and slots, network programming, and various aspects of optimizing your application.

By the end of the book, you will be confident to design and customize GUI applications that meet your client’s expectations and understand the best practice solutions for common problems.

Who this book is for

This intermediate-level book is designed for those who want to develop software using Qt 6. If you want to improve the visual quality and content presentation of your software application, this book is for you. Prior experience in C++ programming is required.

What this book covers

Chapter 1, Look-and-Feel Customization with Qt Designer, shows you how to design your program’s user interface using both Qt Creator and Qt Design Studio.

Chapter 2, Event Handling – Signals and Slots, covers topics related to the signals and slots mechanism provided by Qt 6, which allows you to handle your program’s event callbacks with ease.

Chapter 3, States and Animations with Qt and QML, explains how to animate your user interface widgets by empowering the state machine framework and the animation framework.

Chapter 4, QPainter and 2D Graphics, covers how to draw vector shapes and bitmap images on screen using Qt’s built-in classes.

Chapter 5, OpenGL Implementation, demonstrates how to render 3D graphics in your program by integrating OpenGL into your Qt project.

Chapter 6, Transitioning from Qt5 to Qt6, covers how you can transition your Qt 5 project to Qt 6 and discusses the differences between the two versions.

Chapter 7, Using Network and Managing Large Documents, shows you how to set up an FTP file server and then create a program that helps you to transfer files to and from it.

Chapter 8, Threading Basics – Asynchronous Programming, covers how to create multithreading processes in your Qt 6 application and run them simultaneously to process heavy calculations.

Chapter 9, Building a Touchscreen Application with Qt 6, explains how to create a program that works on a touchscreen device.

Chapter 10, JSON Parsing Made Easy, shows how to process data in the JSON format and use it together with the Google Geocoding API to create a simple address finder.

Chapter 11, Conversion Library, covers how to convert between different variable types, image formats, and video formats using Qt’s built-in classes as well as third-party programs.

Chapter 12, Accessing Databases with SQL Driver and Qt, explains how to connect your program to a SQL database using Qt.

Chapter 13, Develop Web Applications Using Qt WebEngine, covers how to use the web rendering engine provided by Qt and develop programs that empower web technology.

Chapter 14, Performance Optimization, shows you how to optimize your Qt 6 application and speed up its processing.

To get the most out of this book

You will need the following software/hardware to try the learnings from this book:

Software/hardware covered in the book	Operating system requirements
Qt Creator 12.0.2	Windows, macOS, or Linux
Qt Design Studio	Windows, macOS, or Linux
SQLiteStudio	Windows, macOS, or Linux

If you are using the digital version of this book, we advise you to type the code yourself or access the code from the book’s GitHub repository (a link is available in the next section). Doing so will help you avoid any potential errors related to the copying and pasting of code.

Download the example code files

You can download the example code files for this book from GitHub at https://github.com/PacktPublishing/QT6-C-GUI-Programming-Cookbook---Third-Edition-/tree/main. If there’s an update to the code, it will be updated in the GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: “A slot function called on_pushButton_clicked() will now appear in both mainwindow.h and mainwindow.cpp.”

A block of code is set as follows:

import QtQuick
import QtQuick.Window
Window {
   visible: true
   width: 640
   title: qsTr("Hello World")
}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

width: 128;
 	height: 128;
 	x: -128;
 	y: parent.height / 2;

Any command-line input or output is written as follows:

find_package(Qt6 REQUIRED COMPONENTS Network)
target_link_libraries(mytarget PRIVATE Qt6::Network)

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “Select Application (Qt) under the Projects window, and then select Qt Widgets Application.”

Tips or important notes

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Get in touch

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