You can apply animation by default as well. Updating the sort descriptors will cause the view to refresh immediately. With dynamic sorts, you can apply new sort descriptors directly to your list of fetched items backed by the property wrapper. Exploring Dynamic Sortingĭynamic sorting is another new feature in iOS 15. Next, you’ll move on to creating dynamic sorting behavior. managedObjectContext environment variable.īuild and run, and the app will function just as it did before. This allows ContentView, and all its child views, to use the view context from the. You are now accessing the view context directly from PersistenceManager and adding it to the environment. Update the environment variable in AppMain to the following: Let persistenceManager = PersistenceManager.sharedĬore Data will now lazily initialize entities when needed, so this property doesn’t have to be there to “warm up” the Core Data stack. Locate and delete the following property near the top of the class: You can remove some boilerplate code because of this. With iOS 15, lazy entity resolution solves that problem. ![]() If a view attempted to access the view context before setup, you would most likely see a crash. ![]() Prior to iOS 15, you would need to set up your Core Data stack before adding it to the environment. IOS 15 adds a small convenience with lazy entity resolution. You’ll adapt this view throughout the tutorial to perform dynamic sorting, add search via dynamic predicates and update the list to add sections for organization. You’ll see a standard implementation of an property wrapper to fetch a list of Besties sorted by [ This is also the point where, if you don’t have any, the sample friends are added to the database.įinally, open ContentView.swift. You’ll see the persistenceManager property is initialized immediately and then passed into the SwiftUI environment for use in child views. You won’t need to make any changes to this class for the tutorial. The setup is standard - you initialize an NSPersistentContainer and use that to load the persistent stores. This class handles Core Data setup and save operations. You can remove a friend, if they were mean, by swiping to delete, or you can edit one by tapping them, but the main point of this tutorial is to work with the list, so you’ll have a quick tour of the code to orient yourself, then get started. You can tap the + button on the top right to add a new Bestie, if the built-in ones don’t do it for you:Īfter you save, the new Bestie shows up in your list: The app - called Besties - lets you track your friends’ names, where you met them and the date you met. Open the starter project and take a peek around. In this tutorial, you’ll build a Core Data app that helps you track information about your best friends - your besties! Don’t worry if you’re the lonesome type, the app comes with a set of pre-loaded imaginary friends for you to play with. ![]() There’s a lot to cover time to get started! Getting Startedĭownload the starter project by clicking the Download Materials button at the top or bottom of the tutorial. Update existing fetch requests with new sort criteria. ![]() In this tutorial, you’ll learn about all the exciting new features released with iOS 15 for SwiftUI apps that use Core Data. iOS 15 also brings some ease-of-use updates to SwiftUI, such as more straightforward configuration. You can now dynamically apply sorts and filters to lists and see the results update immediately. But if you're a beginner, this is the book you need.IOS 15 offers some powerful new features for SwiftUI when used with Core Data. Note that if you are already an expert this book is probably not for you. Tutorials for Xcode has a set of step-by-step video tutorials based on Swift that teach beginners how to make iOS apps for the iPhone and iPad. Learn how to create your own apps for iPhone and iPad using Xcode and the Swift programming language.
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