Preview SwiftUI views with bindings using @Previewable

Xcode 16 introduced the Previewable macro, making it easier to preview SwiftUI views with bindings. By annotating dynamic properties like @State in a #Preview body with @Previewable, we can pass them as bindings to views directly.

Here is an example on how we can easily setup a fully interactive preview for a basic counter view that accepts a binding:

struct CounterView: View {
    @Binding var count: Int
    
    var body: some View {
        VStack {
            Text("Count: \(count)")
            Button("Increment count") {
                count += 1
            }
        }
    }
}

#Preview {
    @Previewable @State var count = 0
    CounterView(count: $count)
}

This example creates an interactive preview where the count value can be updated in real-time using the provided button.

Xcode preview showing count 3 and increment button

@Previewable is supported on iOS 17, macOS 14, and other platforms.

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