Book Image

SwiftUI Essentials – iOS 14 Edition

By : Neil Smyth
Book Image

SwiftUI Essentials – iOS 14 Edition

By: Neil Smyth

Overview of this book

Do you want to create iOS apps with SwiftUI, Xcode 12, and Swift 5.3, and want to publish it on the app store? This book helps you achieve these skills with a step-by-step approach. This course first walks you through the steps necessary to set up an iOS development environment together and introduces Swift Playgrounds to learn and experiment with Swift—specifically, the Swift 5.3 programming language. After establishing key concepts of SwiftUI and project architecture, this course provides a guided tour of Xcode in SwiftUI development mode. The book also covers the creation of custom SwiftUI views and explains how these views are combined to create user interface layouts, including the use of stacks, frames, and forms. One of the more important skills you’ll learn is how to integrate SwiftUI views into existing UIKit-based projects and explain the integration of UIKit code into SwiftUI. Finally, the book explains how to package up a completed app and upload it to the app store for publication. Along the way, the topics covered in the book are put into practice through detailed tutorials, the source code for which is also available for download. By the end of this course, you will be able to build your own apps for iOS 14 using SwiftUI and publish it on the app store. The code files for the book can be found here: https://www.ebookfrenzy.com/retail/swiftui-ios14/
Table of Contents (56 chapters)
56
Index

52.4 Handling UIKit Delegation and Data Sources

Delegation is a feature of UIKit that allows an object to pass the responsibility for performing one or more tasks on to another object and is another area in which extra steps may be necessary if events are to be handled by a wrapped UIView.

The UIScrolledView, for example, can be assigned a delegate which will be notified when certain events take place such as the user performing a scrolling motion or when the user scrolls to the top of the content. The delegate object will need to conform to the UIScrolledViewDelegate protocol and implement the specific methods that will be called automatically when corresponding events take place in the scrolled view.

Similarly, a data source is an object which provides a UIView based component with data to be displayed. The UITableView class, for example, can be assigned a data source object to provide the cells to be displayed in the table. This data object must conform with the UITableViewDataSource...