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Please help me understand when SwiftUI subviews are re-initialized
See below playground code: import SwiftUI import PlaygroundSupport struct InnerView: View {   @Binding var text: String   @State private var startedChange = false   var body: some View {     Text("Hello").onAppear {       if !self.startedChange {         DispatchQueue.main.asyncAfter(deadline: .now() + 1.0) {           self.text = "cat"         }         DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {           self.text = "cheetah"         }         self.startedChange = true       }     }   } } struct ContentView: View {   @State private var animalName = "dog"   var body: some View {     VStack {       InnerView(text: $animalName)       Text(animalName)     }   } } PlaygroundPage.current.setLiveView(ContentView()) The bottom Text(animal.name) alternates irregularly between "cat" and "cheetah," in an infinite loop of race conditions. I expected the text to change to "cat" after one second and then "cheetah" after another. I would not have expected    @State private var startedChange = false to be initialized more than once. Where is my mental model wrong? (Xcode 12.0)
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811
Sep ’20
AttributeGraph: cycle detected
Hi all!When presenting a specific modal sheet in a SwiftUI project, I consistently get a ton of console output like:=== AttributeGraph: cycle detected through attribute 290 ===Like, a couple hundred of these logs. It appears to be accompanied by a stutter/slowdown in the UI, but there's no crash and everything looks to be in the right place.Is the "cycle" here some sort of ARC retain cycle? Is it SwiftUI-specific? (I'm asking here because I've never seen this warning in a classic UIKit project.) Where can I go to learn more about this?Thanks!
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17k
Dec ’19