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)

Drawing a custom shape

SwiftUI's drawing functionality permits more than just using the built-in shapes: creating a custom shape is just a matter of creating a Path component with the various components and then wrapping it in a Shape object.

In this recipe, we will work through the basics of custom shape creation, implementing a simple rhombus, which is a geometric shape with four equal straight sides that resembles a diamond.

To create a custom shape in SwiftUI, our class must conform to the Shape protocol, whose only function, path(in: CGRect), provides a rectangle that represents the frame where the shape will be rendered as a parameter, and returns a Path struct that is the description of the outline of the shape.

The Path struct has several drawing primitives that permit us to move the point, add lines and arcs, and so on. This allows us to define the outline of the shape.

Using a Path object resembles a bit of the old educative language, Logo, where you are...