Book Image

Cross-Platform Development with Qt 6 and Modern C++

By : Nibedit Dey
Book Image

Cross-Platform Development with Qt 6 and Modern C++

By: Nibedit Dey

Overview of this book

Qt is a cross-platform application development framework widely used for developing applications that can run on a wide range of hardware platforms with little to no change in the underlying codebase. If you have basic knowledge of C++ and want to build desktop or mobile applications with a modern graphical user interface (GUI), Qt is the right choice for you. Cross-Platform Development with Qt 6 and Modern C++ helps you understand why Qt is one of the favorite GUI frameworks adopted by industries worldwide, covering the essentials of programming GUI apps across a multitude of platforms using the standard C++17 and Qt 6 features. Starting with the fundamentals of the Qt framework, including the features offered by Qt Creator, this practical guide will show you how to create classic user interfaces using Qt Widgets and touch-friendly user interfaces using Qt Quick. As you advance, you'll explore the Qt Creator IDE for developing applications for multiple desktops as well as for embedded and mobile platforms. You will also learn advanced concepts about signals and slots. Finally, the book takes you through debugging and testing your app with Qt Creator IDE. By the end of this book, you'll be able to build cross-platform applications with a modern GUI along with the speed and power of native apps.
Table of Contents (17 chapters)
Section 1: The Basics
Section 2: Cross-Platform Development
Section 3: Advanced Programming, Debugging, and Deployment

Integrating QML with JS

QML has a good integration with JS and uses JavaScript Object Notation (JSON)-like syntaxes, allowing expressions and methods to be defined as JS functions. It also permits developers to import JS files and use the existing functionality. The QML engine provides a JS environment that has some limitations compared to the JS environment provided by a web browser. The logic for a Qt Quick application can be defined in the JS. The JS code can be written inline inside the QML file, or in a separate JS file.

Let's look at how to use inline JS inside a QML document. The following example demonstrates the btnClicked() inline JS function. The method is called when the Button control is clicked:

import QtQuick
import QtQuick.Window
import QtQuick.Controls
Window {
    width: 640; height: 480;
    visible: true
    title: qsTr("QML JS integration")
    function btnClicked...