SwiftUI: Pass binding to object initializer inside of init function

Question

In my App i want to initialize an @StateObject property that takes a binding in its initializer. I created an example project to try fixing this problem.

struct ContentView: View {
    @StateObject var myClass: MyClass
    @State var showColor: Bool = false
    
    init() {
        self._myClass = StateObject(wrappedValue: MyClass(showColor: $showColor))  // This does not work
    }
    
    var body: some View {
        VStack {
            if showColor {
                Image(systemName: "globe")
                    .resizable()
                    .foregroundColor(showColor ? .accentColor : .black)
                    .frame(width: 50, height: 50)
            }
            Button {
                myClass.doSomething()
            } label: {
                Text("Do Something")
                    .padding()
                    .background(Color.blue)
                    .foregroundColor(Color.white)
                    .cornerRadius(10)
            }
        }
        .padding()
    }
}

The MyClass class looks like this:

class MyClass: ObservableObject {
    @Binding var showColor: Bool

    init(showColor: Binding<Bool>) {
        self._showColor = showColor
    }

    func doSomething() {
        self.showColor.toggle()
    }
}

The doSomething should toggle the showColor of ContentView.

I tried to initialize the variable inside the init function before creating the MyClass Object. Also the approach to use State or StateObject initializer and wrap the value does not work. Furthermore i tried to use weak var and pass the ContentView to myClass but thats not allowed by xCode (SwiftUI). Now i am at a point where i have no idea how to solve that problem, can anyone help?

Answer 1

You need to change showColor to @Published inside your Class and initialise your class inside the View like this:

@StateObject var myClass: MyClass = MyClass()

And instead of using:

.foregroundColor(showColor ? .accentColor : .black)

Use this:

.foregroundColor(myClass.showColor ? .accentColor : .black)