Learning SwiftUI

Example project to learn a few features of iOS, Swift and SwiftUI

Introduction

In case you want to build an iOS app on iOS 13 and you need to exchange data with another app (e. g. an watchOS app) the shared container is a good solution. This project shows how to write data to a file in a shared container and how read the file again.

Prerequisite

You need to register an app group. The documentation explains the details and the steps: https://developer.apple.com/documentation/xcode/adding_capabilities_to_your_app

Save and Load Data – NSKeyedArchiver NSKeyedUnarchiver

In a previous project I used NSKeyedUnarchiver.unarchiveObjects(withFile path: String) to read from a file in a shared container. Unfortunately this function is now deprecated in iOS 13. From the Xcode developer documentation I found NSKeyedUnarchiver.unarchiveTopLevelObjectWithData as an alternative function, but using it in my project seemed to be tricky.

This project shows how to write data to a file in a shared container and how read the file again.

Documentation: https://developer.apple.com/documentation/foundation/nskeyedunarchiver?language=swift

Resources

Playground auf dem iPad: https://www.apple.com/de/swift/playgrounds/

Language Reference: https://swift.org

Tutorial: https://www.hackingwithswift.com/read/de/0/1/xcode-installieren-und-einen-playground-erstellen

SwiftUI Documentation

Apple Tutorials

https://developer.apple.com/tutorials/swiftui/

WWWDC 2019 Videos

Introducing SwiftUI:

https://developer.apple.com/videos/play/wwdc2019/204

SwiftUI Essentials

https://developer.apple.com/videos/play/wwdc2019/216/

SwiftUI Cheat Sheet

https://fuckingswiftui.com/

https://goshdarnswiftui.com/

Swift 5.1 references for busy coders

https://swiftly.dev

Hacking with Swift

https://www.hackingwithswift.com/articles

SWIFTUI and Storyboard:

https://www.raywenderlich.com/3715234-swiftui-getting-started

A deeper understanding of SwiftUI

https://www.egeniq.com/blog/deeper-understanding-swiftui

Apple Human Interface Guidelines – Gestures

https://developer.apple.com/design/human-interface-guidelines/ios/user-interaction/gestures/

Hacking Swift

What’s the difference between @ObservedObject, @State, and @EnvironmentObject?

https://www.hackingwithswift.com/quick-start/swiftui/whats-the-difference-between-observedobject-state-and-environmentobject