Book Image

Test-Driven iOS Development with Swift - Fourth Edition

By : Dr. Dominik Hauser
Book Image

Test-Driven iOS Development with Swift - Fourth Edition

By: Dr. Dominik Hauser

Overview of this book

Test-driven development (TDD) is a proven way to find software bugs earlier on in software development. Writing tests before you code improves the structure and maintainability of your apps, and so using TDD in combination with Swift 5.5's improved syntax leaves you with no excuse for writing bad code. Developers working with iOS will be able to put their knowledge to work with this practical guide to TDD in iOS. This book will help you grasp the fundamentals and show you how to run TDD with Xcode. You'll learn how to test network code, navigate between different parts of the app, run asynchronous tests, and much more. Using practical, real-world examples, you'll begin with an overview of the TDD workflow and get to grips with unit testing concepts and code cycles. You'll then develop an entire iOS app using TDD while exploring different strategies for writing tests for models, view controllers, and networking code. Additionally, you'll explore how to test the user interface and business logic of iOS apps and even write tests for the network layer of the sample app. By the end of this TDD book, you'll be able to implement TDD methodologies comfortably in your day-to-day development for building scalable and robust applications.
Table of Contents (17 chapters)
1
Section 1 –The Basics of Test-Driven iOS Development
5
Section 2 –The Data Model
9
Section 3 –Views and View Controllers
13
Section 4 –Networking and Navigation

Chapter 5: Building a Structure for ToDo Items

iOS apps are often developed using a design pattern called Model-View-Controller (MVC). In this pattern, each class, struct, or enum is either a model object, view, or controller. Model objects are responsible for storing data. They should be independent of the kind of presentation provided by the UI. For example, it should be possible to use the same model object for an iOS app and a command-line tool on macOS.

View objects present the data. They are responsible for making the objects visible (or hearable, in the case of a VoiceOver-enabled app) for the user. Views are special for the device that the app is executed on. In the case of a cross-platform app, view objects cannot be shared. Each platform needs an implementation of a view layer.

Controller objects communicate between the model and view objects. They are responsible for making the model objects presentable.

We will use MVC for our to-do app because it is one of the...