How to blur View with Animation in SwiftUI?

Question

I am blurring a View depending on the Scene Phase. I also added withAnimation { ... }, however, the Blur-Transition happens without any Animation. Check out my Code:

@main struct ExampleApp: App {
    @Environment(\.scenePhase) var scenePhase
    @State private var blurRadius: CGFloat = 0

    var body: some Scene {
        WindowGroup {
            RootView()
                .blur(radius: blurRadius)
                .onChange(of: scenePhase, perform: { value in
                    switch value {
                        case .active : withAnimation { blurRadius = 0 }
                        case .inactive: withAnimation { blurRadius = 15 }
                        @unknown default: print("Unknown")                    
                    }
                })
        }
    }
}

Does anyone have an Idea why the Blur-Status changes without any Animation?

Thank you for your help.

Answer 1

Although this behavior doesn't seem to work correctly as the root node inside an App, it does seem to work if you move the blur and animation inside the View:

struct RootView: View {
    @Environment(\.scenePhase) var scenePhase
    @State var blurRadius : CGFloat = 0
    
    var body: some View {
        Text("Hello, world!")
            .blur(radius: blurRadius)
            .onChange(of: scenePhase, perform: { value in
                switch value {
                case .active : withAnimation { blurRadius = 0 }
                case .inactive: withAnimation { blurRadius = 15 }
                @unknown default: print("Unknown")
                }
            })
    }
}