在iOS的包文件的AppDelegate中添加如下代码

// Required for the quick_actions package
@available(iOS 9.0, *)
override func application(_ application: UIApplication, performActionFor shortcutItem: UIApplicationShortcutItem, completionHandler: @escaping (Bool) -> Void) {
    let controller : FlutterViewController = window?.rootViewController as! FlutterViewController
    
    let channel = FlutterMethodChannel(name: "plugins.flutter.io/quick_actions", binaryMessenger: controller.binaryMessenger)
    channel.invokeMethod("launch", arguments: shortcutItem.type)
    }

最终结果：

import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    GeneratedPluginRegistrant.register(with: self)
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
  
// Required for the quick_actions package
@available(iOS 9.0, *)
override func application(_ application: UIApplication, performActionFor shortcutItem: UIApplicationShortcutItem, completionHandler: @escaping (Bool) -> Void) {
    let controller : FlutterViewController = window?.rootViewController as! FlutterViewController
    
    let channel = FlutterMethodChannel(name: "plugins.flutter.io/quick_actions", binaryMessenger: controller.binaryMessenger)
    channel.invokeMethod("launch", arguments: shortcutItem.type)
    }
}