NEW: My new book Pro SwiftUI is out now – level up your SwiftUI skills today! >>

Xcode 12 enviornmentObject in WKHostController fatal error at runtime.

Forums > watchOS

Just starting the journey of swiftui, but I don't understand why this works for the contentview preview and not during runtime. (I'm using the simulator.)

class HostingController: WKHostingController<ContentView> {
    let appState = AppState()
    override var body: ContentView {
        return ContentView().environmentObject(appState) as! ContentView

preview works

struct ContentView_Previews: PreviewProvider {
    static let appState = AppState()
    static var previews: some View {
        Group {

The error I receive is "Could not cast value of type AppState to SwiftUI.AnyView." I understand the error, but I thought this was the correct way of setting a environmentObject to the contentView. So did something change in Xcode 12/WatchOS 7? My AppState is a class with ObservableObject protocol.


Hacking with Swift is sponsored by Essential Developer

SPONSORED Join a FREE crash course for mid/senior iOS devs who want to achieve an expert level of technical and practical skills – it’s the fast track to being a complete senior developer! Hurry up because it'll be available only until October 1st.

Click to save your free spot now

Sponsor Hacking with Swift and reach the world's largest Swift community!

Archived topic

This topic has been closed due to inactivity, so you can't reply. Please create a new topic if you need to.

All interactions here are governed by our code of conduct.

Unknown user

You are not logged in

Log in or create account

Link copied to your pasteboard.