如何在macOS中监听电源按钮事件？

import Cocoa

@NSApplicationMain
class AppDelegate: NSObject, NSApplicationDelegate {
    
    func applicationDidFinishLaunching(_ aNotification: Notification) {
        let workspace = NSWorkspace.shared
        let notificationCenter = workspace.notificationCenter
        notificationCenter.addObserver(self, selector: #selector(powerButtonPressed), name: NSWorkspace.willPowerOffNotification, object: nil)
    }
    
    @objc func powerButtonPressed() {
        // 执行一些操作，例如显示警告对话框
        let alert = NSAlert()
        alert.messageText = "电源按钮被按下"
        alert.informativeText = "您确定要关闭电源吗？"
        alert.addButton(withTitle: "取消")
        alert.addButton(withTitle: "关闭电源")
        let response = alert.runModal()
        
        if response == .alertSecondButtonReturn {
            // 用户点击了关闭电源按钮
            // 执行关闭电源的操作
        }
    }
    
    func applicationWillTerminate(_ aNotification: Notification) {
        // 清理资源等操作
    }
}