Hide Title Bar in SwiftUI App for macCatalyst

Question

How can I hide the Title Bar in the new SwiftUI App Protocol?

Since the AppDelegate.swift and SceneDelegate.swift protocols are gone, I cant follow this documentation anymore: https://developer.apple.com/documentation/uikit/mac_catalyst/removing_the_title_bar_in_your_mac_app_built_with_mac_catalyst

I can't implement this code:

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?    
    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        guard let windowScene = (scene as? UIWindowScene) else { return }
        #if targetEnvironment(macCatalyst)
        if let titlebar = windowScene.titlebar {
            titlebar.titleVisibility = .hidden
            titlebar.toolbar = nil
        }
        #endif
    }
}

Hope it's still possible with the new AppProtocol..

Thanks in advance

You can use `withHostingWindow` (from https://stackoverflow.com/a/63276688/12299030) to find own window and then do what's needed. — Asperi, Dec 10 '20 at 17:19
@Asperi, thanks for your response, thanks to your answer I was able to hide the titlebar. I'll post the answer, but I still hope Apple adds official support soon. — John, Dec 10 '20 at 22:39

score 14 · Accepted Answer · answered Dec 10 '20 at 22:42

14

This is how to hide the titlebar:

struct ContentView: View {
    var body: some View {
        ZStack {
            Text("Example UI")
        }
        .withHostingWindow { window in
            #if targetEnvironment(macCatalyst)
            if let titlebar = window?.windowScene?.titlebar {
                titlebar.titleVisibility = .hidden
                titlebar.toolbar = nil
            }
            #endif
        }
    }
}

extension View {
    fileprivate func withHostingWindow(_ callback: @escaping (UIWindow?) -> Void) -> some View {
        self.background(HostingWindowFinder(callback: callback))
    }
}

fileprivate struct HostingWindowFinder: UIViewRepresentable {
    var callback: (UIWindow?) -> ()

    func makeUIView(context: Context) -> UIView {
        let view = UIView()
        DispatchQueue.main.async { [weak view] in
            self.callback(view?.window)
        }
        return view
    }

    func updateUIView(_ uiView: UIView, context: Context) {
    }
}

answered Dec 10 '20 at 22:42

John

297
2
12

UIKit is our everything! :D – imike Dec 14 '20 at 01:57
@imike Yes, i look forward to the time where SwiftUI will have everything to :) – John Dec 14 '20 at 17:10
A better approach is to create a subclass of UIView and implement its willMove:toWindow:, call the callback there, and skip the async. This way there is no flicker and the titlebar is hidden immediately when the view appears. – Jaka Jančar Feb 02 '21 at 17:44
I added the `if let titlebar` conditional from the `.withHostingWindow` modifier, right into my AppDelegate, in `didFinishLaunchingWithOptions` and it worked perfectly! – dbDev May 17 '23 at 18:27

Adam · Answer 2 · 2020-12-14T01:52:47.750

1

On your Scene, set .windowStyle(_:) to HiddenTitleBarWindowStyle().

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
        .windowStyle(HiddenTitleBarWindowStyle())
    }
}

EDIT: Ah crap. While this API is supposedly available for Mac Catalyst according to the online documentation, it looks like it’s not actually marked as such in frameworks so you can’t use it.

edited Dec 14 '20 at 01:52

answered Dec 11 '20 at 02:05

Adam

4,405
16
23

And how can i get to a scene? – John Dec 11 '20 at 16:16
You usually create scenes in @main, e.g. WindowGroup. So set windowStyle on WindowGroup. – Adam Dec 12 '20 at 17:35
i tried that, but there is no option for that. – John Dec 13 '20 at 00:17
Ah sorry, the online documentation says windowStyle(_:) is available for Mac Catalyst but that doesn’t actually seem to be true. Hopefully Apple adds it! – Adam Dec 14 '20 at 01:54
No problem! I hope it to, it’s a must cause it makes your app look so much better. – John Dec 14 '20 at 17:09
Works like a charm in macOS 11. Thank you – XY L Dec 28 '20 at 07:06

Hide Title Bar in SwiftUI App for macCatalyst

2 Answers2