How do I restrict an application to only one window in SwiftUI for macOS? Many Apple applications such as the Notes and the Developer app do not allow creation of another Window. I am wondering how to go about implementing similar behavior in SwiftUI.
I found that this behavior is allowed by default. Essentially, I am trying to eliminate this option here for New Window:
To do this, you need to change the Scene your app uses. WindowGroup implements a multi-window interface, so as long as you're using WindowGroup, you'll have several app behaviors that are associated with a multi-window app.
Use Window instead.
I wrote a blog post about it at https://www.optionalmap.com/posts/swiftui_single_window_app/
Window instead of WindowGroup – it automatically removed the tab-related menu items for me.
I discovered a way to get rid of the option to create a new window using the .commands modifier in your App struct
var body: some Scene {
WindowGroup {
ContentView()
}
.commands {
CommandGroup(replacing: CommandGroupPlacement.newItem) {
EmptyView()
}
}
}
The answer above will work but if you haven't got any workarounds in place app store will reject it because there won't be any possibility for the user to create a new window when closing the previous one. So in order to get your app to work again the user needs to quit the app completely and reopen again, which is against Apple's macOS human interface guidelines
