Book Image

Hands-On GUI Application Development in Go

By : Andrew Williams
Book Image

Hands-On GUI Application Development in Go

By: Andrew Williams

Overview of this book

Go is often compared to C++ when it comes to low-level programming and implementations that require faster processing, such as Graphical User Interfaces (GUIs). In fact, many claim that Go is superior to C++ in terms of its concurrency and ease of use. Most graphical application toolkits, though, are still written using C or C++, and so they don't enjoy the benefits of using a modern programming language such as Go. This guide to programming GUIs with Go 1.11 explores the various toolkits available, including UI, Walk, Shiny, and Fyne. The book compares the vision behind each project to help you pick the right approach for your project. Each framework is described in detail, outlining how you can build performant applications that users will love. To aid you further in creating applications using these emerging technologies, you'll be able to easily refer to code samples and screenshots featured in the book. In addition to toolkit-specific discussions, you'll cover more complex topics, such as how to structure growing graphical applications, and how cross-platform applications can integrate with each desktop operating system to create a seamless user experience. By delving into techniques and best practices for organizing and scaling Go-based graphical applications, you'll also glimpse Go's impressive concurrency system. In the concluding chapters, you'll discover how to distribute to the main desktop marketplaces and distribution channels. By the end of this book, you'll be a confident GUI developer who can use the Go language to boost the performance of your applications.
Table of Contents (25 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Comparison of GUI Toolkits
Index

Building an image viewer


Since the Fyne toolkit includes a canvas API and image handling similar to the Shiny project, it makes sense to also compare with the image viewer application that we created in Chapter 8Shiny – Experimental Go GUI API. Let's start, as usual, with the basic application layout.

Layout

As we will be working with canvas APIs, as well as widgets and layouts, we will need to start by importing most of the Fyne sub-packages. In addition to canvas, where we get the basic image APIs, we will also use the theme package for accessing icons and the app package to launch our application. We don't need to import the image libraries, such as image/jpeg, because Fyne image widgets import them for us:

import (
   "fyne.io/fyne"
   "fyne.io/fyne/app"
   "fyne.io/fyne/canvas"
   "fyne.io/fyne/layout"
   "fyne.io/fyne/theme"
   "fyne.io/fyne/widget"
)

As with any Fyne application, we start by creating an application using app.New() and then create a window for the application by calling...