Book Image

SwiftUI Cookbook

By : Giordano Scalzo, Edgar Nzokwe
Book Image

SwiftUI Cookbook

By: Giordano Scalzo, Edgar Nzokwe

Overview of this book

SwiftUI is an innovative and simple way to build beautiful user interfaces (UIs) for all Apple platforms, right from iOS and macOS through to watchOS and tvOS, using the Swift programming language. In this recipe-based book, you’ll work with SwiftUI and explore a range of essential techniques and concepts that will help you through the development process. The recipes cover the foundations of SwiftUI as well as the new SwiftUI 2.0 features introduced in iOS 14. Other recipes will help you to make some of the new SwiftUI 2.0 components backward-compatible with iOS 13, such as the Map View or the Sign in with Apple View. The cookbook begins by explaining how to use basic SwiftUI components. Then, you’ll learn the core concepts of UI development such as Views, Controls, Lists, and ScrollViews using practical implementation in Swift. By learning drawings, built-in shapes, and adding animations and transitions, you’ll discover how to add useful features to the SwiftUI. When you’re ready, you’ll understand how to integrate SwiftUI with exciting new components in the Apple development ecosystem, such as Combine for managing events and Core Data for managing app data. Finally, you’ll write iOS, macOS, and watchOS apps while sharing the same SwiftUI codebase. By the end of this SwiftUI book, you'll have discovered a range of simple, direct solutions to common problems found in building SwiftUI apps.
Table of Contents (15 chapters)

Fetching remote data using Combine and visualizing it in SwiftUI

A common characteristic most mobile apps have is that they fetch data from a remote web service.

Given the asynchronous nature of the problem, it is often problematic when this is implemented in the normal imperative world.

However, it suits the reactive world nicely, as we'll see in this recipe.

We are going to implement a simple weather app, fetching the current weather and a 5-day forecast from OpenWeather, a famous service that also has a free tier.

After fetching the forecast, we present the result in a list view, with the current weather fixed on the top.

Getting ready

We start by creating a SwiftUI app called WeatherApp.

To use the service, we must create an account on OpenWeather.

Go to the OpenWeather signup page (https://home.openweathermap.org/users/sign_up) and fill it with your data:

Figure 9.6 – OpenWeather signup page

After confirming the login...