Qt SDK

QML is the language that KDE is written in, and from what I’ve read about it, it seems very useful for creating all kinds of computer displays, so I am very interested in learning about it. It’s like HTML. CSS and JavaScript all rolled into one, except its for creating native applications that run on your desktop, instead of web applications that run in an Internet browser.

The Qt SDK includes tools you can use to develop desktop, laptop, tablet, smartphone and embedded applications. You can get it from the Qt Company’s website. It is easy to install and includes the Qt Creator IDE. You can use Qt from your command line or with the code editor of your choice. New users should select the default settings when installing the SDK.

Like HTML, QML is a markup language composed of types enclosed in curly brackets, just like HTML tags enclosed in the less than and greater than brackets. It is designed for speed and readability for developers programming user interfaces. The front end of your application, the part you see on your computer, is built with QML extended with JavaScript. The backend is built with QML enhanced C++.

Qt 6 is the current iteration of Qt, Qt Creator and QML. Qt Creator is the IDE that is built with QML, specifically for programming in QML and other languages. Qt Quick is your primary weapon for using C++, QML and JavaScript to build some awesome applications for your desktop, laptops and tablets and for your smartphones.

Qt 6 is made of modules. Modules are libraries that you can put together to build any number of applications. Essential modules are required for a Qt-enabled platform. Qt Add-on modules are optional. SQLite is included in the Qt SDK by default. You can also use other databases like MySQL or PostgreSQL.

Traditional Qt technologies. Developed for desktop computers, were not all that great for developing smartphone user interfaces. Qt Quick is the solution to that problem. Using the HTML like QML and JavaScript for developing your front-end user interface and C++ for your native back-end technology, enables the best of both the front and back end of your applications.

Qt comes fully equipped with a standard runtime environment called qmlscene. You can also write your own custom runtime. You are not locked into using any particular libraries, you can use third party libraries, rather than the default libraries included with the Qt SDK. You can also extend Qt yourself. Qt also supports a variety of application models, like console, desktop user interface and touch user interface.

Qt Creator is the default cross-platform IDE for Qt. You can use Qt Creator on Windows, Mac or Linux. You must register your Qt Kit. A Qt Kit is a set of tools that recognize each other and can work together. You need to register the version of Qt, the compiler you are using, the device you are using Qt on and some other settings. You can do so in Settings > Build & Run.

Qt Creator organizes your source code into projects. Applications can be minimal projects, they can use Widgets, Qt Quick, or Qt Quick and controls. You can even build HTML 5 or Python projects with Qt Creator.

Source: Qt5 Cadaques, JRyannel, JThelin, 2020.