how do i pass a "@State var purchaseManager" as environment to a child view? purchaseManager is @Observable.

To pass a @State variable like @State var purchaseManager as an environment object to a child view in SwiftUI, you need to follow these steps:

1. Declare the Observable Object: Ensure that purchaseManager conforms to the ObservableObject protocol.

   class PurchaseManager: ObservableObject {
       // Your properties and methods here
   }
   

2. Initialize the State Variable: Initialize the @State variable in your parent view.

   struct ParentView: View {
       @State var purchaseManager = PurchaseManager()
       
       var body: some View {
           ChildView()
               .environmentObject(purchaseManager)
       }
   }
   

3. Use the Environment Object in the Child View: In the child view, use the @EnvironmentObject property wrapper to access the purchaseManager.

   struct ChildView: View {
       @EnvironmentObject var purchaseManager: PurchaseManager
       
       var body: some View {
           // Use purchaseManager here
       }
   }
   

This way, the purchaseManager state variable is passed down to the child view as an environment object, allowing the child view to observe and react to changes in purchaseManager.

For more details on state management in SwiftUI, you can refer to the SwiftUI essentials session from WWDC 2024.