What is @state in the swiftUI?
Asked on 2025-06-16
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In SwiftUI, @State is a property wrapper used to create a source of truth for a view. When you mark a view property with @State, SwiftUI manages the storage of that property and provides it back for the view to read and write. This allows the view to react to changes in the state, automatically updating the UI when the state changes.
For example, if you have a view that displays a rating, you can use @State to keep track of the current rating value. When the user interacts with the view, such as by pressing a button to increment or decrement the rating, SwiftUI will notice the change in state and update the view accordingly.
Here's a brief explanation from the SwiftUI essentials session:
When you mark a view property with
@State, SwiftUI manages the storage and provides it back for the view to read and write. A binding creates a two-way reference to the state of some other view. SwiftUI maintains the value of this state behind the scenes. When the state changes, SwiftUI calls the view's body again, which returns a new view value, and the result is updated on the screen.
SwiftUI essentials
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