從 cocoa 應用程序單擊菜單時如何處理 window 的關閉操作並具有 Window 的單個實例

Question

我使用菜單項以編程方式創建了 cocoa 應用程序。 當我單擊第一個菜單項時，它應該打開一個 window 並且我只想擁有一個 window 實例，這意味着即使我反復單擊第一個菜單項，它也應該激活我當前的 window。 我還想處理 window 的關閉按鈕操作。 當我關閉它並再次嘗試單擊第一個菜單項時，我的應用程序崩潰了。

下面是我的代碼 n AppDelegate：

import Cocoa

class AppDelegate: NSObject, NSApplicationDelegate {
    
    
    
    var statusItem: NSStatusItem!
    lazy var window: NSWindow = NSWindow(
        contentRect: NSRect(x: 0, y: 0, width: 550, height: 300),
        styleMask: [.miniaturizable, .closable, .titled],
        backing: .buffered, defer: false)
    let myViewController = ViewController()
    func applicationDidFinishLaunching(_ aNotification: Notification) {
        statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.variableLength)
        if let button = statusItem.button {
            button.image = NSImage(systemSymbolName: "1.circle", accessibilityDescription: "1")
        }
        
        setupMenus()
        
    }
    
    func setupMenus() {
        // 1
        let menu = NSMenu()
        
        // 2
        let one = NSMenuItem(title: "Open Network Share Url's", action: #selector(didTapOne) , keyEquivalent: "1")
        menu.addItem(one)
        
        
        let two = NSMenuItem(title: "Reconnect", action: #selector(didTapTwo) , keyEquivalent: "2")
        menu.addItem(two)
        
        menu.addItem(NSMenuItem.separator())
        
        menu.addItem(NSMenuItem(title: "Quit", action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q"))
        
        // 3
        statusItem.menu = menu
    }
    
    private func changeStatusBarButton(number: Int) {
        if let button = statusItem.button {
            button.image = NSImage(systemSymbolName: "\(number).circle", accessibilityDescription: number.description)
        }
    }
    
    @objc func didTapOne() {
        changeStatusBarButton(number: 1)
        window.center()
        window.title = "Open Network Share Url's"
        window.makeKeyAndOrderFront(nil)
        window.contentViewController = myViewController
        NSApp.activate(ignoringOtherApps: true)
    }
    @objc func didTapTwo() {
        changeStatusBarButton(number: 2)
        
    }

}

Answer 1

這解決了我的問題

 if window == nil {
            window = NSWindow(
                      contentRect: NSRect(x: 0, y: 0, width: 550, height: 300),
                      styleMask: [.miniaturizable, .closable, .titled],
                      backing: .buffered, defer: false)
                window?.center()
                window?.title = "Open Network Share Url's"
                window?.contentViewController = myViewController
                window?.isReleasedWhenClosed = false
                window?.makeKeyAndOrderFront(self)
             
                  
            } else {
                window?.makeKeyAndOrderFront(self)
            }