SwiftUI macOS cannot change main menu when a NavigationView is present

Question

I try to change some items of the main menu in my SwiftUI macOS app. I don't have macOS Catalyst yet, where the UIKit and UIMenuBuilder comes into play. I want to create my app for macOS versions below Catalyst as well.

I added an AppDelegate where I want to change the main menu by removing certain entries and add a key shortcut to the edit > delete command.

Everything works fine until I add a NavigationView to the view stack:

import Cocoa
import SwiftUI

class AppDelegate: NSObject, NSApplicationDelegate {
    func applicationDidFinishLaunching(_ aNotification: Notification) {
        let mainMenu = NSApplication.shared.mainMenu
        
        // this works
        mainMenu!.removeItem(mainMenu!.item(withTitle: "File")!)
        mainMenu!.item(withTitle: "Help")!.isHidden = true
        
        // the following lines have no effect
        let key = String(utf16CodeUnits: [unichar(NSBackspaceCharacter)], count: 1) as String
        let del = mainMenu!.item(withTitle: "Edit")!.submenu!.item(withTitle: "Delete")
        del!.keyEquivalent = key
        del!.keyEquivalentModifierMask = NSEvent.ModifierFlags.command
        del!.action = #selector(foobar)
        
        // no item is added to Edit menu
        let newItem = NSMenuItem(title: "Foobar", action: #selector(foobar), keyEquivalent: "D")
        mainMenu!.item(withTitle: "Edit")!.submenu!.addItem(newItem)
    }
    
    @objc func foobar() {
        print("foobar")
    }
}

@main
struct testApp: App {
    #if os(macOS)
        @NSApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    #endif
    
    var body: some Scene {
        WindowGroup {
            NavigationView {
                Text("hi")
            }
            .frame(width: 300, height: 200, alignment: .center)
        }
    }
}

When you remove the NavigationView in testApp and only Show Text("hi"), all commands from my AppDelegate work well. However, when you have a NavigationView somewhere in your UI, the .removeItem and .isHidden = true still work, but the rest does not.

Why does having a NavigationView somewhere in your UI (it doesn't have to be the top one, can also be more layers between) enable me to add a key shortcut to a menu item? Is this a bug? If yes, is this a known bug? If no, why is it happening?

Should I build the main menu completely on my own instead of using the default one created by the app?

SwiftUI macOS cannot change main menu when a NavigationView is present

0 Answers0