Book Image

Application Development with Qt Creator - Third Edition

By : Lee Zhi Eng, Ray Rischpater
Book Image

Application Development with Qt Creator - Third Edition

By: Lee Zhi Eng, Ray Rischpater

Overview of this book

Qt is a powerful development framework that serves as a complete toolset for building cross-platform applications, helping you reduce development time and improve productivity. Completely revised and updated to cover C++17 and the latest developments in Qt 5.12, this comprehensive guide is the third edition of Application Development with Qt Creator. You'll start by designing a user interface using Qt Designer and learn how to instantiate custom messages, forms, and dialogues. You'll then understand Qt's support for multithreading, a key tool for making applications responsive, and the use of Qt's Model-View-Controller (MVC) to display data and content. As you advance, you'll learn to draw images on screen using Graphics View Framework and create custom widgets that interoperate with Qt Widgets. This Qt programming book takes you through Qt Creator's latest features, such as Qt Quick Controls 2, enhanced CMake support, a new graphical editor for SCXML, and a model editor. You'll even work with multimedia and sensors using Qt Quick, and finally develop applications for mobile, IoT, and embedded devices using Qt Creator. By the end of this Qt book, you'll be able to create your own cross-platform applications from scratch using Qt Creator and the C++ programming language.
Table of Contents (19 chapters)
1
Section 1: The Basics
7
Section 2: Advanced Features
12
Section 3: Practical Matters

Marking strings for localization

All the way back in Chapter 1, Getting Started with Qt Creator, I told you to always mark your strings for localization using the tr and qsTr functions: tr for C++ and qsTr for QML strings. Doing so has two key advantages:

  • It enables Qt to find every string that needs localization.
  • If you install a Qt translator object in your application and provide a translation file, the strings you wrap with these functions are automatically replaced by their localized equivalent.

Let's examine the use of tr in more detail. All Qt objects that include the Q_OBJECT macro in their declaration include the tr function. You've seen it with one argument, as follows:

button = new QPushButton(tr("&Quit"), this); 

The leading & in the string isn't for the tr function, but it is for the keyboard accelerators; you can prefix a letter...