SwiftUI 6 AttributeGraph warnings in console

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Created 6h

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On a MacBook Air M4 running macOS Sequoia 15.7.7, the following tiny code does warn inside the Xcode 26.3.

Here is the whole console output: === AttributeGraph: cycle detected through attribute 109592 === === AttributeGraph: cycle detected through attribute 109592 === === AttributeGraph: cycle detected through attribute 110216 === === AttributeGraph: cycle detected through attribute 110216 === === AttributeGraph: cycle detected through attribute 110284 === === AttributeGraph: cycle detected through attribute 110284 === === AttributeGraph: cycle detected through attribute 110216 === === AttributeGraph: cycle detected through attribute 109592 === === AttributeGraph: cycle detected through attribute 109592 === === AttributeGraph: cycle detected through attribute 110216 ===

Here is the full code: import SwiftUI

@main struct myApp: App { var body: some Scene { WindowGroup { BaseView() } } }

struct BaseView: View { @State private var isWorking: Bool = false

var body: some View {
    Button("Go") {
        Task {
            // AttributeGraph warnings
            await MainActor.run { isWorking = true }
            await MainActor.run { isWorking = false }

            // No warnings at all

// DispatchQueue.main.async { isWorking = true } // DispatchQueue.main.async { isWorking = false } } } .disabled(isWorking) .padding() } }

You can see with DispatchQueue.main.async {...}, warnings aren't there.

After a few days struggling with different AI support (Claude, ChatGPT, Perplexity), I didn't find any way to fix my own code. This tiny code is just there to show the issue.

I tested multiple workarounds without finding one that fits to my app context.

Thanks in advance for your support.

Answer 1

DTS Engineer OP

Apple

1h

Thanks for the very interesting post.

I’m a little confused and I’m guessing too much for a Monday I think. The reason you are seeing this AttributeGraph: cycle detected warning comes down to how Swift Concurrency, I think.

However because your code is a minimal reproducible example, the correct fix depends on what you are actually doing between isWorking = true and isWorking = false in your real app. I don’t see how that code will produce anything.

In SwiftUI, Button actions are implicitly isolated to the @MainActor. When you create a Task { ... } inside a button action, that Task should inherits the MainActor. Because your Task is already on the MainActor, calling await MainActor.run { ... } does not actually suspend or switch threads. It should executes synchronously.

You are setting isWorking = true and then instantly setting isWorking = false in the exact same runloop without any code or anything to run between them?

If your real app does some heavy calculations or data parsing between the two state changes? You are accidentally blocking the MainActor? You need to move that work off the MainActor so the UI has time to update.

Looking forward to other engineers interpretation to make sure I didn’t missed the mark completely.

Albert  WWDR