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

47.7 Widget Provider

The widget provider is responsible for providing the content that is to be displayed on the widget and must be implemented to conform to the TimelineProvider protocol. At a minimum, it must implement the following methods:

getSnapshot() – The getSnapshot() method of the provider will be called by WidgetKit when a single, populated widget timeline entry is required. This snapshot is used within the widget gallery to show an example of how the widget would appear if the user added it to the device. Since real data may not be available at the point that the user is browsing the widget gallery, the entry returned should typically be populated with sample data.

getTimeline() - This method is responsible for assembling and returning a Timeline instance containing the array of widget timeline entries that define how and when the widget content is to be updated together with an optional reload policy value.

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