Book Image

Hands-On Mobile and Embedded Development with Qt 5

By : Lorn Potter
Book Image

Hands-On Mobile and Embedded Development with Qt 5

By: Lorn Potter

Overview of this book

Qt is a world-class framework, helping you to develop rich graphical user interfaces (GUIs) and multi-platform applications that run on all major desktop platforms and most mobile or embedded platforms. The framework helps you connect the dots across platforms and between online and physical experience. This book will help you leverage the fully-featured Qt framework and its modular cross-platform library classes and intuitive APIs to develop applications for mobile, IoT, and industrial embedded systems. Considerations such as screen size, device orientation changes, and small memory will be discussed. We will focus on various core aspects of embedded and mobile systems, such as connectivity, networking, and sensors; there is no IoT without sensors. You will learn how to quickly design a flexible, fast, and responsive UI that looks great. Going further, you will implement different elements in a matter of minutes and synchronize the UI elements with the 3D assets with high precision. You will learn how to create high-performance embedded systems with 3D/2D user interfaces, and deploy and test on your target hardware. The book will explore several new features, including Qt for WebAssembly. At the end of this book, you will learn about creating a full software stack for embedded Linux systems using Yocto and Boot to Qt for Device Creation.
Table of Contents (23 chapters)
Title Page
Dedication
About Packt
Foreword
Contributors
Preface
Index

Tips, tricks, and suggestions


Qt for WebAssembly is treated by Qt as a cross platform build. It is an emerging technology and, as such, some features required may need special settings configuration to be changed or enabled. There are a few things you need to keep in mind when using it as a target.

Here, I run through some tips regarding Qt for WebAssembly.

Browsers

All major browsers now have support for loading WebAssembly. Firefox seems to load fastest, although Chrome has a configuration that can be set to speed it up (look at chrome://flags for #enable-webassembly-baseline). Mobile browsers that come with Android and iOS also work, although these may run into out of memory errors, depending on the application being run.

Qt 5.13 for WebAssembly has added experimental support for threads, which rely onSharedArrayBuffer support in the browsers. This has been turned off by default, due to Spectre vulnerabilities, and need to be enabled in the browsers.

In Chrome, navigate to chrome://flags and...