[Solved] How do I implement Undo & Redo in SwiftUI using SwiftData in iOS17 Beta 4+ – Swiftui

The Problem:

In SwiftUI with SwiftData library and Core Data, how can undo and redo functionality be effectively implemented for user entry forms in iOS 17 Beta 4+ such that changes made to the form fields can be reversed and restored with a button click, similar to the undo/redo functionality available with the device shake gesture or keyboard buttons, but without the confirmation dialog?

The Solutions:

Solution 1: Update Values On Submit

The undo operation doesn’t perform the expected changes because it’s undoing every keystroke on the TextField. To have it undo the submitted value, you need to update the entity with the final value only when the user presses submit.

Here’s how to do it:

1. Define a @State property to hold a local copy of the trading entity:

   @State private var localTradingEntity: TradingEntity
   

2. Initialize the local trading entity with the passed entity in init:

    init(entity: TradingEntity) {
        self.localTradingEntity = entity
    }
   

3. In the body of the view, use the local trading entity for the TextField and add an .onSubmit modifier to update the entity when the user presses submit:

   VStack(spacing: 12) {
       LabeledContent("Name") {
           TextField("required", text: $localTradingEntity.name)
               .onSubmit {
                   tradingEntity = localTradingEntity
               }
       }
   }
   

This way, the undo operation will undo the submitted value instead of every keystroke.

Video Explanation:

The following video, titled "Solving Equations with Undo Tables - YouTube", provides additional insights and in-depth exploration related to the topics discussed in this post.

Algebra can be hard! In this video, I show you how you can use an Undo Table to understand an algebra equation and figure out how to solve ...