I get nil error since I changed my project to use 'objectWillChange.send()'. Because I needed to update the view manually since it doesn't update itself for custom carousel view(because of core data?).

If I write "1" and tap the next button(NavigationLink)

Console log page.name: 1 catch error: nilError

Here is the codes.

AddPage Class

class AddPage: ObservableObject {
@Environment(\.presentationMode) var presentation
@Environment(\.managedObjectContext) var moc

func addPage(item: String) {

    if item != "" {

        let page = Page(context: self.moc)
        page.name = item

        do {
            print("page.name: \(page.name ?? "Unknown")")
            try self.moc.save()
        } catch {
        print("catch: \(error)")
        }

        objectWillChange.send()
        presentation.wrappedValue.dismiss()
    }
}
}

AddPageView

@ObservedObject var add = AddPage()  

NavigationLink(destination: ContentView()){
Text("Next")
    .background(
        Rectangle()
            .frame(width: 330, height: 60, alignment: .center)
    )
    .onTapGesture {
        add.addPage(item: pageName)
    }
}

SceneDelegate Class

added only

var addpage = AddPage()
let contentView = ContentView()
            .environment(\.managedObjectContext, context)
            .environmentObject(addpage)

Can someone please help me..?

Thank you so much for your reply!! You saved my time so much!