SceneDelegate: NSToolbarItem.Identifier.supplementarySidebarTrackingSeparatorItemIdentifier

SceneDelegate.swift

//
//  SceneDelegate.swift
//  Snippet
//
//  Created by Seb Vidal on 30/01/2022.
//

import UIKit

class SceneDelegate: UIResponder, UIWindowSceneDelegate, NSToolbarDelegate {
    var window: UIWindow?

    func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
        if let windowScene = scene as? UIWindowScene {
            let window = UIWindow(windowScene: windowScene)
            let backgroundViewController = BackgroundViewController()

            window.rootViewController = backgroundViewController
            self.window = window
            window.makeKeyAndVisible()
        }
        
        #if targetEnvironment(macCatalyst)
        setupToolbar()
        #endif
    }

    #if targetEnvironment(macCatalyst)
    func setupToolbar() {
        let toolbar = NSToolbar()
        toolbar.delegate = self
        window?.windowScene?.titlebar?.toolbar = toolbar
        window?.windowScene?.titlebar?.titleVisibility = .hidden
    }
    
    func toolbarDefaultItemIdentifiers(_ toolbar: NSToolbar) -> [NSToolbarItem.Identifier] {
        return [NSToolbarItem.Identifier("navigationButton"), .supplementarySidebarTrackingSeparatorItemIdentifier, NSToolbarItem.Identifier("otherButton")]
    }
    
    func toolbarAllowedItemIdentifiers(_ toolbar: NSToolbar) -> [NSToolbarItem.Identifier] {
        return [NSToolbarItem.Identifier("navigationButton"), .supplementarySidebarTrackingSeparatorItemIdentifier, NSToolbarItem.Identifier("otherButton")]
    }
    
    func toolbar(_ toolbar: NSToolbar, itemForItemIdentifier itemIdentifier: NSToolbarItem.Identifier, willBeInsertedIntoToolbar flag: Bool) -> NSToolbarItem? {
        switch itemIdentifier {
            case NSToolbarItem.Identifier("navigationButton"):
                let barButtonItem = UIBarButtonItem(image: UIImage(systemName: "arrow.left"), style: .plain, target: self, action: #selector(nop(_:)))
                return NSToolbarItem(itemIdentifier: itemIdentifier, barButtonItem: barButtonItem)
            case NSToolbarItem.Identifier("otherButton"):
                let barButtonItem = UIBarButtonItem(image: UIImage(systemName: "plus"), style: .plain, target: self, action: #selector(nop(_:)))
                return NSToolbarItem(itemIdentifier: itemIdentifier, barButtonItem: barButtonItem)
            default:
                break
        }
        
        return NSToolbarItem(itemIdentifier: itemIdentifier)
    }
    
    @objc func nop(_ sender : NSObject) {}
    #endif
}