tableview with data from user defaults swift

#Tableview with data from user defaults swift how to
#Tableview with data from user defaults swift code
#Tableview with data from user defaults swift free

This includes updating the labels, the table, animating the screen components, and all those pretty things we like to look at. UI logic is the part that deals with the user interface, i.e. This could be known as “processing” in simpler terms.

This includes actions such as updating the data, deleting items from a list, formatting a data type, and that kind of thing. It ensures the models are updated, the data is processed in a way that is human readable, and so on. What is the difference, you ask?īusiness logic is the programming that manages the communication between an end user interface and databases.

MVVMīefore we go any further, there are two very integral parts of any iOS app that you should understand: UI logic and business logic.

The most important thing you will need is the willingness to learn and follow along with the migration. As you might have guessed, the MVVM branch has the MVVM flavor of the app and the MVC has the MVC flavor. The repo has three branches: master, MVVM, and MVC.

The app we will be working with, which is hosted on a GitHub repository.

#Tableview with data from user defaults swift how to

The app we will be working on is very simple, so you will only need an understanding of the syntax and how to debug.

A general understanding of the Swift language.

Xcode 8.3 or later this is the IDE used to build iOS apps.

The app also persists the data so that you still maintain the state of the app (number of items, item done or not) after it goes to the background. It can create a to-do activity, delete a to-do activity, and mark an activity as done. The app has all the basic functionalities that will show the patterns. In order to understand the MVC and MVVM design patterns, we will be building a to-do app. We will learn how to use one common iOS pattern, MVVM, in this post.

#Tableview with data from user defaults swift code

Imagine how much more difficult it will be for someone who did not write the code to navigate it. When you go back to debug, it may be hard to figure out where some things are and why you even did them in the first place. Say you solve a problem without any particular design, and at the moment, it works. Why use design patterns? We use them because design patterns are typically easier to reuse and debug than an unproven design. In this post, we’ll be concentrating on MVVM and MVC. Other common design patterns include MVP (Model-view-presenter) and VIPER ( here is a little write up that describes them). If you’ve built a product, you’ve probably built using MVC. While MVC is a very common and easy-to-implement design pattern, it has been faulted as very inefficient while working with large code bases. MVVM (Model-View-Viewmodel) and MVC (Model-View-Controller) are both design patterns. This could mean that it tries to configure cells with data that does not yet exist in the fetchedObjects array.Design patterns are reusable solutions to common problems in code. Pitfall 2: Not using the cell provider dataĭuring the animation from one snapshot to another the data source will create cells for animating changes. Although we could’ve created this ourselves too it’s better to just use performFetch and make the fetched results controller responsible for configuring the data. The main reason this is wrong is that the resulting snapshot contains a collection of NSManagedObject instances while a snapshot of NSManagedObjectID is expected.

Snapshot.appendItems(withIdentifiers: items, intoSectionWithIdentifier: section)ĭiffableDataSource.applySnapshot(snapshot, animatingDifferences: false) Let diffableDataSource = UICollectionViewDiffableDataSource(collectionView: collectionView) The creation of a data source looks as follows: In the examples given in this post, we’re focussing on collection views but the same technique can be used for table views. Creating a Diffable Data Source for Core DataĪdopting diffable data sources in Core Data starts by creating a new data source instance. If you want to know a quick way to set up diffable data sources throughout your project, check out my blog post Diffable Data Sources Adoption with Ease. It's available only until July 30th, so click to get it now!

#Tableview with data from user defaults swift free

If you’re a mid/senior iOS developer looking to improve your skills and salary level, join this 100% free online crash course. FREE iOS Architect Crash Course for a limited time!