SwiftUI retain cycle

import SwiftUI

struct ContentView: View {
    @ObservedObject var toastManager = ToastManager()

    @State var offset: CGFloat = 60

    init() {
        // This actually throws an error: Escaping closure captures mutating 'self' parameter
        toastManager.onShow = { self.onShow() }
    }

    var body: some View {
        ZStack(alignment: .bottom) {
            ChildView().environmentObject(toastManager)

            if toastManager.show {
                Text(toastManager.text).offset(x: 0, y: offset).onTapGesture {
                    self.hide()
                }
            }
        }
    }

    func onShow() {
        withAnimation {
            self.offset = 0
        }
    }

    func hide() {
        withAnimation {
            self.offset = 60
        }
    }
}

struct ChildView: View {
    @EnvironmentObject var toastManager: ToastManager

    var body: some View {
        VStack {
            Spacer()
            Button(action: { self.toastManager.show(text: "Test toast") }) {
                Text("Show toast")
            }
            Spacer()
        }
    }
}

class ToastManager: ObservableObject {
    var onShow: () -> Void = {}

    @Published var text = ""

    @Published var show = false

    func dismiss() {
        show = false
    }

    func show(text: String) {
        self.text = text
        show = true
        onShow()
    }
}